Basil of Caesarea — as excerpted in the Catena Aurea on Luke 4:1-4

“Or, the Lord remained for forty days untempted, for the devil knew that He fasted, yet hungered not, and dared not therefore approach Him. Hence it follows: And he eat nothing in those days. He fasted indeed, to shew that He who would gird Himself for struggles against temptation must be temperate and sober.”