In the 14th century, Hesychasm was attacked by an Italian cleric, Barlaam of Calabria, who brought charges of heresy against one of its advocates, Gregory Palmas (1296-1359), who was later to become Archbishop of Thessalonica. The latter defended the practice, and his views were later confirmed by three synods in Constantinople. Hesychasm became an official practice of the Orthodox Church and became popular, especially after the publication of a collection of texts called the Philokalia in Russia in 1782.