A viewer informed me this is Saint Antony, the desert Father, the monk.

The Enc. Brit. has " born c. 251, Koma, near al-Minyā, Heptanomis [Middle Egypt], Egypt.
died Jan. 17?, 356, Dayr Mārī Antonios hermitage, near the Red Sea; feast day January 17.

A disciple of Paul of Thebes, Anthony began to practice an ascetic life at the age of 20 and after 15 years withdrew for absolute solitude to a mountain by the Nile called Pispir (now Dayr al-Maymūn), where he lived from about 286 to 305. During the course of this retreat, he began his legendary combat against the devil, withstanding a series of temptations famous in Christian theology and iconography. In about 305 he emerged from his retreat to instruct and organize the monastic life of the hermits who imitated him and who had established themselves nearby. When Christian persecution ended after the Edict of Milan (313), he moved to a mountain in the Eastern Desert, between the Nile and the Red Sea, where the monastery Dayr Mārī Antonios still stands. Here he remained, receiving visitors and, on occasion, crossing the desert to Pispir. He ventured twice to Alexandria, the last time (c. 350) to preach against Arianism, a heretical doctrine teaching that Christ the Son is not of the same substance as God the Father.