The Euchites or Messalians were a Christian sect from Mesopotamia they spread to Asia Minor and Thrace. The name 'Messalian' comes from the Syriac word "msallyana", meaning 'one who prays'. The Greek translation is "euchites", meaning the same.

The sect's teaching asserted that:
The essence (ousia) of the Trinity could be perceived by the carnal senses.
The Threefold God transformed himself into a single hypostasis (substance) in order to unite with the souls of the perfect.
God has taken different forms in order to reveal himself to the senses.
Only such sensible revelations of God confer perfection upon the Christian.
The state of perfection, freedom from the world and passion, is therefore attained solely by prayer, not through the church, baptism and or any of the sacraments, which have no effect on the passions or the influence of evil on the soul (hence their name, which means "Those who pray").
Messalians taught that once a person experienced the essence of God they were freed from moral obligations or ecclesiastical discipline. They had male and female teachers whom they honored more than the clergy, the "perfecti".The condemnation of the sect by St John Damascene and Timothy, priest of Constantinople, expressed the view that the sect espoused a sort of mystical materialism. Their critics also accused them of incest, cannibalism and "debauchery" (in Armenia their name came to mean "filthy") but scholars reject these claims.