And when he had fasted forty days and forty nights, he was afterward hungry.
All Commentaries on Matthew 4:2 Go To Matthew 4
George Leo Haydock
AD 1849
Jesus wished to manifest a certain corporeal weakness, arising from his continued fast, that the devil might venture to tempt him; and after a fast of 40 days and 40 nights he was hungry. (Haydock)
Christ was well acquainted with the thoughts of the wicked fiend, and his great desire of tempting or trying him. The devil had learnt that he was come into the world from the songs of the angels at his birth, and from the mouth of the shepherds and of St. John the Baptist. To fast 40 days without being hungry, was certainly far above the strength of man, but to be hungry at any time is inconsistent with God; for which reason our blessed Saviour, that he might not manifestly declare his divinity, was afterwards hungry. (St. Hilary)
On this example, as well as that of Moses and Elias, who also fasted 40 days, the fast of Lent was instituted by the apostles, and is of necessity to be observed according to the general consent of the ancient Fathers. St. Jerome (ep. liv. ad Marcel.) says, we fast 40 days, or make one Lent in a year, according to the tradition of the apostles. St. Augustine (serm. lxix.) says, by the due observance of Lent, the wicked are separated from the good, infidels from Christians, heretics from Catholics. Our Saviour fasted 40 days, not because he stood in need of it, as we do, to subject the unruly members of the body, which lust against the spirit, but to set an example for our imitation. (Haydock)
Another reason might be, to prevent the captious remarks of the Jews, who might object that he had not yet done what the founder of their law, Moses, and after him Elias, had done. (Palacius in Mat.)