Catholics believe that Jesus goes by many titles, such as the Messiah, the Son of God or the Light of the World, but one of the key titles that Jesus is called by is the fullness of God's Revelation. Through fulfilling salvation History; the life, death and resurrection of Jesus Christ, the world made flesh has revealed to us God's plan for salvation and desire for intimacy with humans. Through the deeds and actions of God throughout salvation history, God has managed to reveal himself to his people, but his revelation through creation and the covenants of Abraham and Moses proved to be not enough in guiding humanity to intimate relationship with God as the tendency to sin plagued the intimacy of their relationship. It is through sending Jesus down on earth that God has managed to reveal fully his plan to his people and brought them salvation through the kingdom of God.
Revelation is to make known a mystery or an unknown. When talking about God's revelation we mean the dynamic and continuing process in which God communicates to humans to help them understand about him and what he is like. The purpose of revelation is to ultimately reveal that we are made in the image and likeness of God and how by being authentically human we can develop an intimate relationship with and appreciate our Creator. But because of our first parents humanity has misinterpreted what it means to "be like God". "Seduced by the devil [man] wanted 'to be like God' but 'without God, before God and not in accordance with God" (Catechism of the Catholic Church hereafter CCC, 398) This submission into temptation is called Original Sin. Because of original sin and the mistake of Adam and Eve the original harmony God created with humans has been destroyed. "As sin came in the world though one man and death through sin, death spread to all as all men sinned." (Romans 5:12) Centuries after the fall, Jesus as the redeemer came on this Earth to "save people from the slavery of sin" (CCC601) that plagues us from birth.