15 Learn also another cause. Christ came that He might be baptized, and might sanctify Baptism: He came that He might work wonders, walking upon the waters of the sea. Since then before His appearance in flesh, the sea saw Him and fled, and Jordan was turned back, the Lord took to Himself His body, that the sea might endure the sight, and Jordan receive Him without fear. This then is one cause; but there is also a second. Through Eve yet virgin came death; through a virgin, or rather from a virgin, must the Life appear: that as the serpent beguiled the one, so to the other Gabriel might bring good tidings. Men forsook God, and made carved images of men.
Since therefore an image of man was falsely worshipped as God, God became truly Man, that the falsehood might be done away. The Devil had used the flesh as an instrument against us; and Paul knowing this, says, But I see another law in my members warring against the law of my mind, and bringing me into captivity, and the rest. By the very same weapons, therefore, wherewith the Devil used to vanquish us, have we been saved. The Lord took on Him from us our likeness, that He might save man's nature: He took our likeness, that He might give greater grace to that which lacked; that sinful humanity might become partaker of God. For where sin abounded, grace did much more abound. It behooved the Lord to suffer for us; but if the Devil had known Him, he would not have dared to approach Him. For had they known it, they would not have crucified the Lord of Glory. His body therefore was made a bait to death that the dragon, hoping to devour it, might disgorge those also who had been already devoured. For Death prevailed and devoured; and again, God wiped away every tear from off every face.
Source: Catechetical Lectures (New Advent)