CCC 128 The Church, as early as apostolic times,1 and then constantly in her Tradition, has illuminated the unity of the divine plan in the two Testaments through typology, which discerns in God’s works of the Old Covenant prefigurations of what he accomplished in the fullness of time in the person of his incarnate Son.

CCC 632 The frequent New Testament affirmations that Jesus was “raised from the dead” presuppose that the crucified one sojourned in the realm of the dead prior to his resurrection.2 This was the first meaning given in the apostolic preaching to Christ’s descent into hell: that Jesus, like all men, experienced death and in his soul joined the others in the realm of the dead. But he descended there as Savior, proclaiming the Good News to the spirits imprisoned there.3

CCC 1094 It is on this harmony of the two Testaments that the Paschal catechesis of the Lord is built,4 and then, that of the Apostles and the Fathers of the Church. This catechesis unveils what lay hidden under the letter of the Old Testament: the mystery of Christ. It is called “typological” because it reveals the newness of Christ on the basis of the “figures” (types) which announce him in the deeds, words, and symbols of the first covenant. By this re-reading in the Spirit of Truth, starting from Christ, the figures are unveiled.5 Thus the flood and Noah’s ark prefigured salvation by Baptism,6 as did the cloud and the crossing of the Red Sea. Water from the rock was the figure of the spiritual gifts of Christ, and manna in the desert prefigured the Eucharist, “the true bread from heaven.”7

CCC 1219 The Church has seen in Noah’s ark a prefiguring of salvation by Baptism, for by it “a few, that is, eight persons, were saved through water”:8
The waters of the great flood
you made a sign of the waters of Baptism,
that make an end of sin and a new beginning of goodness.9

CCC 1794 A good and pure conscience is enlightened by true faith, for charity proceeds at the same time “from a pure heart and a good conscience and sincere faith.”10
The more a correct conscience prevails, the more do persons and groups turn aside from blind choice and try to be guided by objective standards of moral conduct.11

1 Cf. I Cor 10:6, 11; Heb 10:l; l Pt 3:21.
2 Acts 3:15; Rom 8:11; I Cor 15:20; cf. Heb 13:20.
3 Cf. I Pt 3:18-19.
4 Cf. DV 14-16; Lk 24:13-49.
5 Cf. 2 Cor 3:14-16.
6 Cf. 1 Pet 3:21.
7 Jn 6:32; cf. 1 Cor 10:1-6.
8 1 Pet 3:20.
9 Roman Missal, Easter Vigil 42: Blessing of Water.
10 1 Tim 5; cf. 8:9; 2 Tim 3; 1 Pet 3:21; Acts 24:16.
11 GS 16.