
Gregory of Nazianzus
Catena Aurea · Lukasevangelium 4
And Jesus being full of the Holy Ghost returned from Jordan, and was led by the Spirit into the wilderness, Being forty days tempted of the devil. And in those days he did eat nothing: and when they were ended, he afterward hungered. And the devil said unto him, If thou be the Son of God, command this stone that it be made bread. And Jesus answered him, saying, It is written, That man shall not live by bread alone, but by every word of God.
(Orat. 40.) He fasted in truth forty days, eating nothing. (For He was God.) But we regulate our fasting according to our strength, although the zeal of some persuades them to fast beyond what they are able.