Christian revelation excludes reincarnation, and speaks of a fulfilment which man is called to achieve in the course of a single earthly existence. Man achieves this fulfilment of his destiny through the sincere gift of self, a gift which is made possible only through his encounter with God. It is in God that man finds full self-realization: this is the truth revealed by Christ. Man fulfils himself in God, who comes to meet him through his Eternal Son. Thanks to God's coming on earth, human time, which began at Creation, has reached its fullness. "The fullness of time" is in fact eternity, indeed, it is the One who is eternal, God himself. Thus, to enter into "the fullness of time" means to reach the end of time and to transcend its limits, in order to find time's fulfilment in the eternity of God.
[Pope John Paul II, Tertio Millennio Adveniente n.9]