Under the Patriarch John III (Scholasticus, 565-577) he was deacon at the Hagia Sophia church; then he became sakellarios (an official who acts as patriarchal vicar for monasteries).
The first known use of it applied to Constantinople is in a letter from the monks of Antioch to John II (518-520) in 518.
The works in Migne attributed to John the Faster [a treatise on Confession (P. G., LXXXVIII, 1889-1918), a shorter work on the same subject (ibid., 1919-1932), "Of Penance, Temperance, and Virginity" (ibid., 1937-1978)] are not authentic.