He was a devout but unorthodox Protestant Christian and, unusually for a member of the Cambridge faculty of the day, he refused to take holy orders in the Church of England, perhaps because he privately rejected the doctrine of the Trinity. Beyond his work on the mathematical sciences, Newton dedicated much of his time to the study of biblical chronology and alchemy, but most of his work in those areas remained unpublished until long after his death.
His book "Philosophiæ Naturalis Principia Mathematica" ("Mathematical Principles of Natural Philosophy"), first published in 1687, laid the foundations for classical mechanics. Newton's Principia formulated the laws of motion and universal gravitation, which dominated scientists' view of the physical universe for the next three centuries. By deriving Kepler's laws of planetary motion from his mathematical description of gravity, and then using the same principles to account for the trajectories of comets, the tides, the precession of the equinoxes, and other phenomena, Newton removed the last doubts about the validity of the heliocentric model of the Solar System.
Perhaps the movement which most influenced Isaac Newton was Rosicrucianism. Though the Rosicrucian movement had caused a great deal of excitement within Europe's scholarly community during the early seventeenth century, by the time Newton had reached maturity the movement had become less sensationalized. However, the Rosicrucian movement still would have a profound influence upon Newton, particularly in regard to his alchemical work and philosophical thought.
The Rosicrucian belief in being specially chosen for the ability to communicate with angels or spirits is echoed in Newton's prophetic beliefs. Additionally, the Rosicrucians proclaimed to have the ability to live forever through the use of the elixir vitae and the ability to produce limitless amounts of time and gold from the use of The Philosopher's Stone, which they claimed to have in their possession. Like Newton, the Rosicrucians were deeply religious, avowedly Christian, anti-Catholic, and highly politicised. Isaac Newton would have a deep interest in not just their alchemical pursuits, but also their belief in esoteric truths of the ancient past and the belief in enlightened individuals with the ability to gain insight into nature, the physical universe, and the spiritual realm.