From the website, Catholic Harbor of Faith and Morals…
by St. Thomas Aquinas
First Sunday of Lent:It was fitting that Christ should be tempted
Jesus was led by the spirit into the desert, to be tempted
by the devil. Matt. iv. i.
Christ willed to be tempted:
1. That He might assist us against our own temptations. St. Gregory says, ” That our Redeemer, who had come on earth to be killed, should will to be tempted was not unworthy of Him. It was indeed but just that he should overcome our temptations by His own, in the same way that He had come to overcome our death by His death.”
2. To warn us that no man, however holy he be, should think himself safe and free from temptation. Whence again His choosing to be tempted after His baptism, about which St. Hilary says, “The devil’s wiles are especially directed to trap us at times when we have recently been made holy, because the devil desires no victory so much as a victory over the world of grace.” Whence too, the scripture warns us, Son, when thou comest to the service of God, stand in justice and in fear, and prepare thy soul for temptation (Ecclus. ii. i).
3. To give us an example how we should over come the temptations of the devil, St. Augustine says, “Christ gave Himself to the devil to be tempted, that in the matter of our overcoming those same temptations He might be of service not only by His help but by His example too.”
4. To fill and saturate our minds with confidence in His mercy. For we have not a high-priest who cannot have compassion on our infirmities, but one tempted in all things, like as we are, without sin (Heb. iv. 15).