The filioque — as understood in the West since the rise of Scholasticism — is, and always will be, unacceptable to the East, because it posits the idea that the Son is a cause within the Godhead and thus undermines the doctrine of the monarchy of the Father.

That said, I will now explain in greater detail what I mean by saying this:

In Eastern Triadology God the Father is the sole personal cause (aitian) of the person (hypostasis) of the Son by generation (gennesin), and of the person (hypostasis) of the Holy Spirit by procession (ekporeusis), and — for the Eastern Fathers — this doctrine of the monarchy of the Father is why there is only one God. Foundational to this approach to the understanding of the Godhead is the teaching of the Cappadocian Fathers (i.e., St. Basil, St. Gregory Nazianzus, and St. Gregory of Nyssa) that there are only two kinds (or types) of properties or characteristics within the Holy Trinity: (1) hypostatic properties, i.e., properties that are unique to only one hypostasis, and by which the three divine hypostaseis are distinguished from each other as their mode of existence (tropos hyparxeos); and (2) essential properties, which are common to all three hypostaseis because the Son and Spirit are one in essence (homoousios) with the Father. These properties are revealed to man through the divine energies, which manifest the Triune God’s presence in creation.

Now bearing in mind this twofold theological distinction without a separation, i.e., the distinction between hypostatic properties and essential properties, it becomes clear that in Eastern Triadology it is impossible for two hypostaseis of the Trinity to possess the same property or characteristic without the third hypostasis also possessing it, because anything that is held in common by two of the divine hypostaseis must necessarily be possessed also by the third divine hypostasis. So, if the Father and the Son are held — in some sense — to be a single principle (i.e., cause) in connection with the existential origin (i.e., the ekporeusis) of the Holy Spirit as hypostasis, it follows that the Spirit too must be one principle with them in His own procession (ekporeusis), which means that the Spirit must cause His own existence, and this is clearly nonsensical. Moreover, if one were to argue that the Father and the Son act in unison as a common principle, while simultaneously excluding the Holy Spirit from this common essential act, it follows that the Father and the Son would be essentially distinct from the Holy Spirit, because by existentially causing the hypostasis of the Holy Spirit they would possess a common (i.e., essential) property that the Spirit lacks, which means that the Holy Spirit would be essentially less than the Father and the Son, and essentially other than the Father and the Son in connection with His own procession (ekporeusis) of origin as hypostasis, and since — in the Western teaching — the Spirit does not possess this common essential property it follows that He is not fully one God with them, and this teaching from an Orthodox perspective involves the heresy of Ditheism. Additionally, the idea that the Father and the Son act as a co-principle (or a single principle) in the procession (ekporeusis) of origin of the Holy Spirit as hypostasis involves not only the sin of Ditheism, but also Sabellian Modalism, because according to the Eastern Fathers the existential procession (ekporeusis) of the Holy Spirit is proper to the Father as hypostasis, i.e., it is not a common essential property of the Godhead, but is instead a hypostatic property of the Father alone, and as such it cannot be shared with the Son without confusing the hypostasis of the Son with the hypostasis of the Father. Clearly the Eastern Churches will never accept the idea that the Father and the Son are a co-principle in the procession (ekporeusis) of the Spirit as hypostasis, since this necessarily entails the heresy of Modalism.

Sadly, the whole Scholastic theory of the Trinity is predicated upon a confusion of person (hypostasis) and essence (ousia), and so the East will never be able to accept the filioque as it has been formulated in the West during the course of the second millennium (i.e., at the Councils of Lyons II and Florence), because to do so would involve the absolute repudiation of the original meaning of the Niceno-Constantinopolitan creed and the Cappadocian theological framework established during the fourth century in order to protect the Church's profession of faith from both Sabellianism and Eunomianism.

Finally, taking into account what I have already said, it is clear that the East will reject anything that makes the Son a cause (immediate, mediate, or instrumental) in the existential procession (ekporeusis) of the hypostasis of the Holy Spirit, because the Spirit as hypostasis receives His eternal origin from the Father alone, and not from or through the Son. Nevertheless, the East has no problem saying that the Spirit as energy, but not as hypostasis, progresses (proienai) from the Father through the Son, and this eternal progression as energy is not merely an economic reality, but is an immanent reality within the Godhead itself, because the divine energy is not reducible to God’s manifestation in creation, but pre-exists creation as its cause, flowing out from the Father, through the Son, in the power of the Holy Spirit, and thus revealing the eternal consubstantial communion of the three divine hypostaseis within the Godhead. I will end by saying that the solution to this thorny issue was proposed by Gregory of Cyprus at the Council of Blachernae (AD 1285), which is why the canons of that council should form the basis for any dialogue in connection with the Holy Spirit's eternal shining forth (eklampsis) through the Son.

The Filioque:  Confusing Hypostatic and Essential Properties in God

by Steven Todd Kaster

Original Version:  16 September 2007 (from a thread at the Phatmass Phorum)

This brief essay was revised and expanded on:

9 October 2023.

Copyright © 2007-2025 Steven Todd Kaster