CCC 460 The Word became flesh to make us “partakers of the divine nature”:1 “For this is why the Word became man, and the Son of God became the Son of man: so that man, by entering into communion with the Word and thus receiving divine sonship, might become a son of God.”2 “For the Son of God became man so that we might become God.”3 “The only-begotten Son of God, wanting to make us sharers in his divinity, assumed our nature, so that he, made man, might make men gods.”4
1 2 Pt 1:4.
2 St. Irenaeus, Adv. haeres. 3, 19, 1: PG 7/1, 939.
3 St. Athanasius, De inc. 54, 3: PG 25, 192B.
4 St. Thomas Aquinas, Opusc. 57, 1-4.