Saint Moses, called Moses the Black, was an escaped slave, and the leader of a group of 75 robbers. He was a large and powerful man, who with his gang terrorized the entire region. Moses was transformed after he and his group attacked a monastery, intending to rob it. The Abbot, whose peaceful and warm manner overwhelmed him, met him. He immediately felt remorse for all his past sins, sincerely repented.
One day, as he was confessing his sins to St Macarios, an angel appeared with a tablet full of his sins. As he confessed, the angel began wiping the tablet clean. The more he confessed, the more the angel wiped, until by the end it was completely clean. After meeting St Macarios and St. Isidore, he completely left his old ways behind him and became a monk.
He gave himself over to prayer and the mortification of the carnal mind with such diligence that he later became a priest of exemplary virtue. Later, St. Moses was ordained to the priesthood - a rare honour among the Desert Fathers - and founded a monastery of 75 monks, the same number as his former group of thieves. He was known for his wisdom, humility, love, and non-judgment of others. Once a brother had been caught in a particular sin, and the Abbot asked St Moses to come to the church and render judgment. He came reluctantly, carrying on his back a leaking bag of sand. When he arrived, the brothers asked him why he was carrying such a thing. He simply said, "This sand is my sins which are trailing out behind me, while I go to judge the sins of another". At that reply, the brothers forgave the offender and returned to focusing on their own salvation rather than the sins of their brother.
In 405 A.D., at age 75, a barbarian tribe come to Scete. St Moses, conscious that he himself had slain other men when he was a thief, awaited them and was slain by them with six other monks. He was a contemporary of Saint Arsenios the Great (commemorated May 8).