1 And Jesus being full of the Holy Ghost, returned from the Jordan, and was led by the Spirit into the desert, 2 For the space of forty days; and was tempted by the devil. . . .
Theophylact: Christ is tempted after His baptism, shewing us that after we are baptized, temptations await us.
Origen: When therefore you read that Jesus was full of the Holy Spirit, and it is written in the Acts concerning the Apostles, that they were filled with the Holy Spirit, you must not suppose that the Apostles were equal to the Savior. For as if you should say, These vessels are full of wine or oil, you would not thereby affirm them to be equally full, so Jesus and Paul were full of the Holy Spirit, but Paul’s vessel was far less than that of Jesus, and yet each was filled according to its own measure. Having then received baptism, the Savior, being full of the Holy Spirit, which came upon Him from heaven in the form of a dove, was led by the Spirit, because, as many as are led by the Spirit, they are the sons of God, but He was above all, especially the Son of God.
Ambrose: By way of example, it was to shew us that the devil envies us, whenever we strive after better things; and that then we must use caution, lest the weakness of our minds should lose us the grace of the mystery.
Gregory: Our enemy was however unable to shake the purpose of the Mediator between God and men. For He condescended to be tempted outwardly, yet so that His soul inwardly, resting in its divinity, remained unshaken.
Scripture from the Douay-Rheims Bible. Commentary from St. Thomas Aquinas, Catena Aurea, Vol. III (London: Rivington, 1843).