God Comes to Man
From the Catechism of the Catholic Church, Simplified
Beyond Human Knowledge (50)
Fortunately, God has revealed his eternal plan by sending his Son, Jesus Christ, and the Holy Spirit (a mystery revealed only in this final age).
God Wants Man to Come near in Jesus (51-53)
God wants all men to have access to him through Christ and in the Holy Spirit (Eph 1:9, 2:18).
Although "dwelling in unapproachable light" (1 Tim 6:16), God wants to communicate his life to man. Man can share in God's nature and live beyond his natural capacity.
God's revelation culminated in the person and mission of Jesus Christ. "The Word of God became the Son of man in order to accustom man to perceive God and to accustom God to dwell in man" (St. Irenaeus).
Revelation Not Destroyed by Sin (54-55)
God manifested himself to our first parents and clothed them with grace.
Even sin did not ruin God's plan because he immediately promised redemption (Gen 3:15). "Again and again you offered a Covenant to man" (Eucharistic Prayer IV).
Salvation to People Groups (56-58)
Sin shattered man's unity. However, God said to Noah, "I am establishing my Covenant with you and your descendants after you" (Gen 9:9). God planned salvation according to groups, "each with its own language, by their families, in their nations" (Gen 10:5).
This division into nations was cosmic, social and religious. However, God's plan was always threatened by polytheism and idolatry.
This Covenant with Noah remained in effect until the proclamation of the Gospel and brought forth many holy people (the just Abel, the king priest Melchizedek, Noah, Daniel, and Job).
Gathered Together in Abraham (59-61)
To gather scattered humanity, God chose Abram and named him Abraham, "the father of many nations" (Gen 17:5).
His descendents (Israel) prepared for the Church and were the root onto which the Gentiles were grafted (Rom 11:17-24).
From Moses to the Prophets (62-64)
God freed his people from Egypt, made a Covenant with them (through Moses on Mt. Sinai) and gave them his law.
Israel is God's priestly people, the first to hear God's Word.
Through the prophets, God proclaimed a radical redemption and told his people to await a new Covenant (Jer 31:31-34). In the Old Testament, God used many women to keep Israel's hopes alive (Sarah, Rebecca, Judith, Esther, etc.). Among these, Mary is the purest figure.