§521

Christ enables us to live in him all that he himself lived, and he lives it in us. "By his Incarnation, he, the Son of God, has in a certain way united himself with each man." We are called only to become one with him, for he enables us as the members of his Body to share in what he lived for us in his flesh as our model:

We must continue to accomplish in ourselves the stages of Jesus' life and his mysteries and often to beg him to perfect and realize them in us and in his whole Church. . . For it is the plan of the Son of God to make us and the whole Church partake in his mysteries and to extend them to and continue them in us and in his whole Church. This is his plan for fulfilling his mysteries in us.