Venerable Achillas, an Egyptian desert father.
St. Achillas was one of the desert fathers of Scetis in Egypt in the fourth and fifth centuries, whose sayings are preserved among those of the elders. He was known for the severity of his fasting and for his discretion toward the brethren.
He is commemorated on January 17.
Feast day
On the New Calendar, Achillas the Venerable is commemorated on January 17. Churches on the Old (Julian) Calendar keep the feast on January 30 of the civil calendar.
Also commemorated on January 17

Theodosios the Great
Saint, Θεοδόσιος ο Μέγας
Holy Emperor Theodosios the Great, who convened the Second Ecumenical Council.