St Cosmas the Hermit lived during the sixth century in the Pharan wilderness of Palestine. An account of the Bikaneia presbyter Abba Basil about St Cosmas is located in the book Spiritual Meadow (Ch. 40) compiled by St John Moschus. He was strict of fasting, a firm defender of the Orthodox Faith and Church dogmas, and profoundly knowledgeable in Holy Scripture and the works of the Church Fathers.

St Cosmas particularly revered the works of St Athanasius the Great and told those to whom he spoke: "If you come across a word of St Athanasius and have no paper, write it upon your clothing." He had the habit to stand at prayer all night Saturday through Sunday.

Having once come to Antioch, he died there, and the patriarch buried his body at his monastery. Abba Basil relates that when he came to venerate the grave of St Cosmas, he found there a beggar, who told him: "It is a great Elder whom you have buried here!" He explained that he had been paralyzed for twelve years, and received healing through the prayers of St Cosmas.