Rudolf Steiner revived the medieval art of the mystery play. 

Mystery plays originally were “vernacular drama in Europe during the Middle Ages ... [M]ystery plays, usually representing biblical subjects, developed from plays presented in Latin by churchmen on church premises and depicted such subjects as the Creation, Adam and Eve, the murder of Abel, and the Last Judgment." — "mystery play." ENCYCLOPÆDIA BRITANNICA, Online, 17 Feb. 2010.

Steiner wrote four mystery plays, attempting to find artistic form for his doctrines. The plays contain various potentially exciting elements, but the results are stilted, consisting mainly of characters standing around, delivering long, declamatory speeches. There is so little action that group readings are recognized as adequate substitutes for full stagings. 

“Although written to be performed on stage, these dramas may be read in a group setting and still have much of the intended effect. The four plays follow in sequence. It is desirable to read then in sequence.” — Cover note for Rudolf Steiner's FOUR MYSTERY PLAYS (Anthroposophical Publishing Co., 1925), GA 14.

Attendance at performances was originally limited to Anthroposophists, but today — with the texts readily available — this restriction has been relaxed.

The central theme of the four-play cycle is the development of human karma through spiritual evolution. In a sense, the protagonist is Anthroposophy itself. The cycle is 

“the representation of a community of contemporary human beings who...find themselves searching for the spirit that belongs to humanity. This was a community...called together by destiny and determined to undergo and overcome the most varied tests of soul on their paths of life. All of the individuals in this ‘initiation drama’ (as Rudolf Steiner once called it) find themselves on the threshold of the awakening to their higher humanity.” — Albert Steffen, quoted by Henry Barnes in A LIFE FOR THE SPIRIT: Rudolf Steiner in the Crosscurrents of Our Time (Anthroposophic Press, 1997), p. 100.

“The four plays...are intended to represent the experiences of the soul during initiation; or in other words, the psychic development of man up to the moment when he is able to pierce the veil and see into the beyond ... This process is known as the ‘Rosicrucian’ initiation — an initiation specially adapted to modern days — the time and manner of which depend on the individual nature and circumstances of each person.

“The four plays form one continuous series, and the characters portrayed are of quite an ordinary kind except that they take more than the usual interest in spiritual matters ... We find amongst them many types — the occult leader and the seeress who explains the coming of Christ. We are shown the spiritual development of an artist, a scientist, a philosopher, a historian, a mystic, and a man of the world; and we hear too the scoffing cynicism of the materialist Fox.” — H. Collison, introduction, FOUR MYSTERY PLAYS.

 —

The plays are THE PORTAL OF INITIATION (1910), THE SOUL’S PROBATION (1911), THE GUARDIAN OF THE THRESHOLD (1912), and THE SOUL’S AWAKENING (1913).

Here are some intriguing scene synopses, generally more dramatic than the scenes themselves. (I will quote from the “Editorial Summaries” in FOUR MYSTERY PLAYS. Some are quite brief, while some — toward the end — are fuller and incorporate directions by Steiner.)

THE PORTAL OF INITIATION

Scene 5: “The subterranean rock temple. The consultation of the hierophants.”

Scene 7: “The Spirit-world. Maria and her soul powers. Theodora's vision of the past incarnation of Maria and Johannes. The scene ends with Benedictus' great mystic utterance.”

Scene 11: “The Temple of the Sun. Destiny and debtors.”

THE SOUL’S PROBATION

Scene 6:  “The 14th century. The meadows by the Castle of the Mystic Knights. Country folk. The Jew. Thomas confesses to the Monk his love for Keane's daughter.”

Scene 11: “Meditation chamber as in Scene 2. Maria defeats Ahriman.”

THE GUARDIAN OF THE THRESHOLD

Scene 1: “The ante-chamber to the rooms of the Mystic League. The reincarnated country folk have been invited to attend a meeting here.”

Scene 6: “The groves of Lucifer and Ahriman and their creatures who dance. Dame Balde's fable.”

Scene 9: “The home of Benedictus, overlooking a factory town. The law of number. The Zodiac.”

THE SOUL’S AWAKENING

Scene 1: “Hilary's business is threatened with disaster because of his attempt to introduce into it his spiritual ideals and occult methods. He has engaged as controller of his machinery, Strader, who is generally known to be a failure because of his impractical inventions. With him comes a group of similar “cranks.” Hilary's old manager is in despair.”

Scene 5: “The Spirit World. This scene needs careful meditation and some knowledge of the author's system. Attention should be given to the indications of the planetary spheres — Mercury, Venus, Sun, Jupiter, and Saturn — to which in turn we may expand after death. Heed should be paid to the warning given by the Guardian of the Threshold. Lucifer here appears as a beneficent guide; so, too, the Other Philia.”

Scene 12: “Ahriman's manner, shape, and speech betray the fact that he is being found out by the followers of Benedictus. Ahriman hopes, however, to catch Strader. Note the satire indulged in at the expense of those occultists, theosophists, and others whose air of superiority makes them a laughing stock. Note also the last lines showing the importance of remembering the dead.”

Scene 15: “Secretary and Nurse. The Secretary's speech. Ahriman's shape is here even more that of the conventional devil than in Scene 12. This is to show that his true nature is now fully grasped by Benedictus and his followers. This is seen in Ahriman's last speech. Note Benedictus' speech about the dead and their messages (p. 293). Benedictus tells Ahriman that one can only serve Good when one does good not for oneself. Ahriman's knowledge of his own final destruction. The defeat and exit of Ahriman. The triumph and initiation of Strader; his future power.”

I won’t elaborate on my own experience of the plays. Instead, here is an evaluation by a sympathetic commentator: 

“[A]s theater, Steiner’s Mystery Dramas are, I think, an acquired taste. Without doubt they deal with the deep concerns of spiritual life and, for those committed to Steiner’s ideas, can provide a moving and transformative experience. But for the uninitiated, they can appear stiff, and redolent somewhat of Sunday school. Even for an audience sympathetic to spiritual ideas, the plays, for my taste at least, suffer from being heavy on message and light on movement. There are many long speeches, and what there is of action seems to consist of the characters’ engaging in extended arguments about the need for a new spiritual vision ... The problem with this is that too extended a stay in the higher realms can lead to boredom. The central character, Benedictus, is a spiritual teacher most likely based on Steiner himself ... All [the others] have gathered to hear Benedictus speak of his experiences in the spiritual worlds ... The poet Christian Morgenstern, who became one of Steiner’s followers, managed to highlight the work’s good points, while faintly acknowledging that as theater, there was still more work to be done. ‘It is not a play,’ he wrote to a friend, but ‘it mirrors worlds of the spirit ... [I]t may well be hundreds of years before there are enough human beings who want this pure, spiritual art.’” — Gary Lachman, RUDOLF STEINER (Jeremy P. Tarcher, 2007), pp. 165-166.

— Compilation and commentary by Roger Rawlings

—

While they may be deficient as dramas,

 Steiner's plays are presented as striking spectacles.

[Painting by R. R., 2010, based on a photo

in THE GOETHEANUM 

(Philosophical-Anthroposophical Press, 1961), p. 21;

the photo includes several figures, but I have limited myself

to the central, sword-wielding Guardian of the Threshold.]

—

Dramatis Personae

Here is a brief list of principle characters who appear in Steiner’s mystery plays. It may or may not prove helpful. Descriptions placed within quotation marks are taken from FOUR MYSTERY PLAYS (Anthroposophical Publishing Co., 1925). Most of these quoted descriptions come from Steiner himself.

Ahriman, a demonic god, lord of a spiritual region.

Albertus Torquatus, a representative of the “element of the devotion.” He is “Master of the Ceremonies in the Mystic League, known as Theodosius in ‘The Portal of Initiation.’”

Astrid, a friend of Maria. Her prototype reveals itself as a “spirit of Maria's soul-powers.” Astrid is a spirit who facilitates “the connection between the Soul and the Cosmos.”

Benedictus, a spiritual teacher, often taken to be a version of Steiner himself. A representative of the “element of the spirit,” Benedictus is Leader of the Temple of the Sun. “Benedictus, the personality in whom a number of his ‘pupils’ recognize the sage who knows the deep spiritual connection of earthly events. In my earlier soul pictures ‘The Portal of Initiation’ and ‘The Soul's Probation,’ he is portrayed as the Hierophant of the Sun-Temple; in ‘The Guardian of the Threshold’ he represents that spiritual movement which seeks to substitute the actual spiritual life of modern times for the merely traditional views upheld therein by the Mystic Brotherhood. In ‘The Soul's Awakening’ Benedictus must no longer be conceived only as a sage who has authority over his pupils but also as having his own soul's destiny interwoven with theirs.”

Bernard Straight, a reincarnated peasant.

Bertha - Joseph Keane’s daughter, Mary Steadfast.

Capesius, a professor and a representative of the “element of the devotion.” 

Casper Hotspur, a reincarnated peasant.

Cecilia, aka the Soul of Theodora, “foster daughter of Keane and sister of Thomas.”

A Child, “whose prototype...reveals itself as a young soul.”

Dame Keane - Felicia Balde.

The “Double” of Johannes Thomasius.

Erminia Stay-at-Home, a reincarnated peasant.

Felicia Balde, wife of Felix Balde. A  representative of the “element of soul,” she is also known as Dame Balde and Dame Keane.

Felix Balde, an herb gatherer who reveals himself as “representative of the Spirit of Nature.” Also a representative of the “element of soul,” he is based on Felix Koguski, who reportedly gave Steiner his first occult initiation. “Felix Balde represent[s] in ‘The Portal of Initiation’ a kind of Nature-mysticism [and later] a subjective mysticism. He appears as Joseph Keane in ‘The Soul's Probation.’”

Ferdinand Fox - whose soul is found “in the realm of Ahriman.” He is the reincarnation of one of “the twelve peasants in ‘The Soul's Probation’.”

Francesca Humble, a reincarnated peasant.

Frederick Clear-Mind, a reincarnated peasant. He manages Hilary's sawmill business.

Frederick Trustworthy,  a representative of the “element of will.” He is “Master of the Ceremonies in the Mystic League. The Reincarnation of the Second Master of the Ceremonies of the Spirit-Brotherhood in ‘The Soul's Probation’, and known as ‘Romanus’ in ‘The Portal of Initiation.’”

George Candid, a reincarnated peasant.

Germanus, “whose prototype...reveals itself as that of the Earth-brain.” He is also known as Magnus Bellicosus.

Gnomes, various.

The Guardian of the Threshold.

Helena,” whose prototype...reveals itself as that of Lucifer.”

Hilary True-to-God, a representative of the “element of the spirit.” He is “Grand Master of the Mystic League, represented in a former incarnation ...as the Grand Master of a Mystic Brotherhood ... [He is an] adept in traditional spiritual life, which, in his case, is accompanied by individual spirit-experience.”

Hilary's Secretary. "He appears in ‘The Guardian of the Threshold’ as Frederick Clear-Mind."

The Jew, Simon - Doctor Strader.

Johannes Thomasius, a painter and a pupil of Benedictus. A representative of the “element of the spirit,” he is also known as Thomas.

Joseph Keane - Felix Balde.

Katherine Counsel, a reincarnated peasant.

Louisa Fear-God, a reincarnated peasant.

Lucifer, a demonic god, lord of a spiritual region.

Luna, a friend of Maria, whose prototype reveals itself as a “spirit of Maria's soul-powers.”  Luna is a spirit who facilitates “the connection between the Soul and the Cosmos.”

Magnus Bellicosus, a representative of the “element of the devotion.” He is “Preceptor of the Mystic League, known as Germanus in ‘The Portal of Initiation.’”

The Manager of Hilary's business of sawmills.

Maria,  Johannes’s partner, a representative of the “element of soul” and a pupil of Benedictus.

Mary Dauntless, a reincarnated peasant.

Mary Steadfast, Dr. Strader’s nurse and a reincarnated peasant. “In ‘The Portal of Initiation’ she is known as ‘The Other Maria’ because the imaginative perception of Johannes Thomasius constructs, under her guise, an imaginative picture of certain nature-forces. Her individuality appears in ‘The Soul's Probation’ as Bertha, Keane's daughter.”

Michael Nobleman, a reincarnated peasant.

The Other Maria, “whose prototype...reveals itself as the Soul of Love.” She is also known as Mary Steadfast.

The Other Philia, “the spiritual being who hinders the union of the soul-powers with the Cosmos.” Or she represents “the element of Love in the world to which the spirit-personality belongs.”

Peasants - a dozen simple country folk who appear in “The Soul’s Probation” and are later reincarnated as various characters, such as Ferdinant Fox.

Phila, a friend of Maria, whose prototype reveals itself as a “spirit of Maria's soul-powers.”  Phila is a spirit who facilitates “the connection between the Soul and the Cosmos.”

Romanus, “whose prototype...reveals itself as that of the Spirit of Action.” He is a Hierophant of the Temple of the Sun. He is also known as Frederick Trustworthy. The name Romanus “expresses the inner state of being to which he has worked upwards during the years which elapse between ‘The Portal of Initiation’ and the ‘Awakening.’ In ‘The Guardian of the Threshold’ the name given him of Frederick Trustworthy is the one by which he is supposed to be known in the physical world, and the name is used there because his inner life has very little to do with the events represented. In ‘The Soul's Probation’ he appears as Second Master of Ceremonies in the medieval Mystic Brotherhood.”

Retardus, “active only as a Spirit-influence.”

The Soul of Theodora. This soul is also known as Cecilia.

The Spirit of Johannes Thomasius' Youth.

The Spirit of the Elements, “conceived as a Spirit-influence.”

The Soul of Ferdinand Fox.

Strader, a doctor and a representative of the “element of will.” He is also “the individual appearing in ‘The Soul's Probation’ as the Jew, Simon.”

Sylphs, various.

Theodosius, “whose prototype...reveals itself as that of the Spirit of Love.” He is a Hierophant of the Temple of the Sun. He is also known as Albertus Torquatus.

Theodora,  a representative of the “element of will.” She is “a Seeress, in whom the Element of Will is changed into a simple gift of prophecy.”

Thomas - Johannes Thomasius.

The Voice of Conscience.

—

Scenes from THE GUARDIAN OF THE THRESHOLD

(photographs, THE GOETHEANUM 

(Philosophical-Anthroposophical Press, 1961), pp. 21 and 25).

—

Below is an item from the Waldorf Watch News,

posted on March 6, 2013. It overlaps some of what you have 

already seen, but it also adds some additional information.

On this date — March 6 — in the year 1913, Rudolf Steiner delivered a lecture that has been preserved as “Errors in Spiritual Investigation: Meeting the Guardian of the Threshold” [see http://wn.rsarchive.org/Lectures/Dates/19130306p01.html].

Here’s a sample:

“Everything that the human being experiences on entering the spiritual world is designated ordinarily as the experience with the Guardian of the Threshold. I tried to describe something concrete about this experience in my Mystery Drama, The Guardian of the Threshold. Here it only need be mentioned that at a certain stage of spiritual development, man learns to know his inner being as it can love itself with the force of an event of nature, as it can be frightened and horrified on entering the spiritual world. This experience of our own self, of the intensified self of that inner being that otherwise never would come before our soul, is the soul-shaking event called the Meeting with the Guardian of the Threshold. Only by having this meeting will one acquire the faculty to differentiate truth from error in the spiritual world.”

Steiner taught that there are actually two Guardians of the Threshold, spiritual beings that we, in a sense, create out of ourselves. We must satisfy these ominous apparitions before we can gain entree to the spirit realm. [See "Guardians".]

The concept of Guardians of the Threshold can be traced far back in the history of mysticism, but Steiner apparently picked up the concept and label from a work of fiction, the novel ZANONI.

“Central to [one’s] spiritual work on inner development is what Rudolf Steiner calls (following Bulwer Lytton, who introduced the term in his Rosicrucian novel ZANONI), the ‘Meeting with the Guardian of the Threshold.’” — Christopher Bamford, editor, START NOW! (Rudolf Steiner Press, 2007) p. 243.

Although the Guardians may be, in more than one sense, purely fictional characters, Steiner took their existence with great seriousness. Thus, in his crucial book, KNOWLEDGE OF THE HIGHER WORLDS AND ITS ATTAINMENT — a book in which he lays out many of his key doctrines and instructions for his followers — he gives the following description of an encounter with one of the Guardians:

“[W]hen the Guardian has [spoken], there arises from the spot where he stands a whirlwind which extinguishes all those spiritual lights that have hitherto illumined the pathway of [the spiritual aspirant’s] life. Utter darkness, relieved only by the rays issuing from the Guardian himself, unfolds before the student. And out of this darkness resounds the Guardian's further admonition: ‘Step not across my Threshold until thou dost clearly realize that thou wilt thyself illumine the darkness ahead of thee; take not a single step forward until thou art positive that thou hast sufficient oil in thine own lamp. The lamps of the guides whom thou hast hitherto followed will now no longer be available to thee.’ At these words, the student must turn and glance backward. The Guardian of the Threshold now draws aside a veil which till now had concealed deep life-mysteries. The family, national, and racial spirits are revealed to the student in their full activity, so that he perceives clearly on the one hand, how he has hitherto been led, and no less clearly on the other hand, that he will henceforward no longer enjoy this guidance. That is the second warning received at the Threshold from its Guardian.” — Rudolf Steiner, KNOWLEDGE OF THE HIGHER WORLDS AND ITS ATTAINMENT (Anthroposophic Press, 1947), chapter 9, "The Guardian of the Threshold", GA 10.

Having accepted a fiction as a reality, and proceeding to embed this “reality” in his teachings, Steiner turned to a fictional (or dramaturgical) form to express his belief in this “reality.” Steiner wrote four “mystery dramas” — essentially religious pageants patterned after medieval stage performances meant to dramatize and express religious mysteries. The difference is that Steiner’s mystery dramas express his Theosophical/Anthroposophical religious doctrines, not the teachings of any mainstream Christian church or sect. Attendance at the performance of mystery dramas — those from the Middle Ages and those from Steiner's pen — is essentially attendance at religious celebrations.

The third of Steiner's dramas is titled “The Guardian of the Threshold.” Here are excerpts from the synopsis provided in FOUR MYSTERY DRAMAS (SteinerBooks, 2007):

“SCENE ONE. A group of twelve persons, representing the ‘general public’ has been invited by a Mystic or Occult Brotherhood ... The Brotherhood is motivated...by the publication of certain books on spiritual science ... The author is Thomasius ... They offer to sponsor his work ... 

“SCENE TWO. Thomasius refuses this offer. In reality, what he has written will be utilized by [the demon] Ahriman, because Thomasius himself is not able to exert full control over his lower self ... He describes an actual encounter with Ahriman on his way to this meeting ... 

“SCENE THREE. Maria unexpectedly meets Capesius in Lucifer’s realm ... Capesius’ soul is a captive of this world ... Maria’s soul has entered Lucifer’s realm for the sake of Thomasius. She witnesses the initiative which Lucifer has taken in order to bind Thomasius to himself ... 

“SCENE FOUR. A quiet, harmonious conversation takes place between Strader and Theodora ... The scene ends, however, on a note of doubt and shock. Lucifer’s machinations have begun their work. 

“SCENE FIVE. Strader seeks comfort in the home of Felicia and Felix Balde ... After [recollecting] his former life, in medieval times, [Strader] has lost interest in the present time and place ... 

“SCENE SIX. Capesius’ soul finds itself carried into the etheric world by mantric words received in earlier times from Benedictus ... Lucifer and Ahriman re-echo the mantric words ... [A] fairy tale of the child of light (‘Imagination’) gives Capesius the inner strength and courage to bring back his ego-consciousness into his earthly body ... 

“SCENE SEVEN. Thomasius, accompanied by Maria, appears before the Guardian of the Threshold ... Because Maria vouches for him, the Guardian lets them both pass into the spiritual world ... 

“SCENE EIGHT. Ahriman in his own domain is not recognized by Hilary ... Strader enters fully aware of Ahriman and is witness to his power over the twelve souls who in their sleep come under his spell ... The scene ends with Thomasius’ initial experience beyond the actual threshold, a renewed encounter with his Double [i.e., his doppelgänger], and his release from Lucifer’s magic spell ... 

“SCENE NINE. Benedictus meets his friends, Capesius and Strader, who have become his pupils ... Thomasius recalls for Maria his shattering experience in Ahriman’s realm ... 

“SCENE TEN. The sanctuary of the Rosicrucian Brotherhood is a symbolic temple with three altars ... The duties at the altars in East, South and West are now taken over by free individuals who, under the guidance of Benedictus, have achieved direct insight into the world beyond the threshold ... The Soul Forces close the play with words of grace.”

Steiner’s four plays are regularly performed by his followers, especially at the Anthroposophical headquarters in Switzerland, the Goetheanum. Don’t go out of your way, but if you ever have a chance, you might want to see if you can bear to sit through a performance. Even sympathetic commentators acknowledge that the plays are a bit hard to take.

“[A]s theater, Steiner’s Mystery Dramas are, I think, an acquired taste ... [T]hey can appear stiff, and redolent somewhat of Sunday school ... [They] suffer from being heavy on message and light on movement. There are many long speeches, and what there is of action seems to consist of the characters’ engaging in extended arguments about the need for a new spiritual vision [i.e., Steiner’s teachings].” — Gary Lachman, RUDOLF STEINER (Jeremy P. Tarcher, 2007), p. 165.

Still, as primers on the bizarre doctrines of Anthroposophy, the plays have their value. Bear in mind, these are the doctrines on which Waldorf education is founded, so you might want to take a gander.