The Rosary is a biblical prayer given to us by God, via the Angel Gabriel at his Annunciation to Our Lady.
Hail, full of grace, the Lord is with thee, blessed art thou amongst women and blessed is the fruit of thy womb.The second portion of the prayer comes from Elizabeth's greeting to Mary.
Blessed are you among women, and blessed is the fruit of your womb! And how has it happened to me, that the mother of my Lord should come to me?
The Biblical origins of the Rosary are further enhanced by the mysteries. Each decade has associated with it, a different set of mysteries. While praying that decade, we are to meditate on these scenes from the life of Christ. When praying the entire 20 decades of the Rosary, we have gone all the way through the life of Christ, from the Mary's "Yes" to God at the Annunciation, to Christ's ministry on earth, His death, Resurrection and Ascension into Heaven, to the descent of the promised Holy Spirit on the Apostles.
The Assumption of the Virgin is based on the idea of Mary as Ark of the Covenant. In the Old Testament, the Ark of the Covenant held the very tablets with which God Himself wrote the ten commandments, and as such, the ark was very special and had to be built to God's exact specifications (Ex 25:9, 39:42-3). In 2 Samuel 6, the Israelites had lost the Ark. When King David sees the Ark being brought back, he says, "Who am I that the ark of the Lord should come to me?" (2 Sam 6:9). This directly foreshadows Elizabeth's prophesy in Luke:"And how has it happened to me, that the mother of my Lord should come to me?" (Luke 1:43)
As the bearer of the Lord (Theotokos) Mary was kept free from sin, not by her own merit, but by God's saving grace. God the Father exists fully outside of time. He is the One who has existed from all time, since He is uncreated. As such, God knew that Mary's answer to His angel would be, "Yes" and He created her without stain of original sin. Without Christ's death on the cross, Mary's salvation would not be possible. Hence, Mary is able to say with all of us, "And my spirit hath rejoiced in God my Saviour." (Luke 1:47)
The Five Joyful Mysteries
1. The Annunciation
2. The Visitation
3. The Nativity
4. The Presentation
5. The Finding in the Temple
The Five Mysteries of Light
1. His Baptism in the Jordan
2. His self-manifestation at the wedding of Cana,
3. His proclamation of the Kingdom of God, with his call to conversion.
4. His transfiguration,
5. His institution of the Eucharist, as the sacramental expression of the Paschal
The Five Sorrowful Mysteries
1. The Agony in the Garden
2. The Scourging at the Pillar
3. The Crowning of Thorns
4. The Carrying of the Cross
5. The Crucifixion
The Five Glorious Mysteries
1. The Resurrection
2. The Ascension
3. The Descent of the Holy Spirit
4. The Assumption
5. The Crowning of the Blessed Virgin