Answer: Because it's a Gospel Prayer
The Rosary is a powerful meditative prayer based on the gospel. The Rosary consists of the following prayers.
Glory Be - “Glory be to the Father, and to the Son, and to the Holy Spirit. As it was in the beginning, is now, and ever shall be, world without end. Amen.
Apostles Creed - “I believe in God, the Father Almighty, Creator of heaven and earth, and in Jesus Christ, his only Son, our Lord, who was conceived by the Holy Spirit, born of the Virgin Mary, suffered under Pontius Pilate, was crucified, died, and was buried. He descended into hell. The third day he arose again from the dead. He ascended into heaven and is seated at the right hand of the Father. From thence he shall come to judge the living and the dead. I believe in the Holy Spirit, the holy Catholic Church, the communion of saints, the forgiveness of sins, the resurrection of the body, and the life everlasting. Amen.”
The Hail Mary is from Luke 1.
Luke1:28 The Archangel Gabriel says: “Hail (Mary), full of grace, the Lord is with thee."
Luke 1:42 Elizabeth filled with the Holy Spirit proclaimed: “Blessed art thou among women, and blessed is the fruit of thy womb, (Jesus).”
“Holy Mary, Mother of God, pray for us sinners, now and at the hour of our death. Amen.” Here we are asking Mother Mary to pray for us.
If you are protestant or do not pray the Rosary, which of these do you disagree with?
The Apostles Creed, Lord's Prayer, Luke 1 (Hail Mary), Glory Be.
Do you disagree with any of these? If yes which one?
We also recite the Hail Holy Queen:
Hail Holy Queen, Mother of mercy, Our life, our sweetness, and our hope. To thee do we cry, poor banished children of Eve. To thee do we send up our sighs, mourning and weeping in this valley of tears. Turn then, most gracious advocate, thine eyes of mercy towards us. And after this, our exile, show unto us the blessed fruit of thy womb, Jesus. O clement O loving O sweet Virgin Mary. Pray for us oh holy mother of God. That we may be made worthy of the promises of Christ. Amen.
As Catholics we believe the Bible when it says all generations will call Mary blessed. We would encourage our protestant brothers and sisters to live out this Gospel as well.
Luke 1: 46-49 "And Mary said: “My soul proclaims the greatness of the Lord; my spirit rejoices in God my savior. For he has looked upon his handmaid’s lowliness; behold, from now on will all ages call me blessed. The Mighty One has done great things for me, and holy is his name."
As Catholics when we pray the Rosary we are calling Mary blessed because the Lord has done great things for Her.
1 Tim. 2:1-4 Paul instructs Christians to pray for each other, meaning it cannot interfere with Christ’s mediatorship: “I urge that prayers, supplications, petitions, and thanksgivings be made for everyone. . . . This is good, and pleasing to God our Savior.”
Revelation 5:8 reveals, intercede for us by offering our prayers to God: “The twenty-four elders fell down before the Lamb, each holding a harp, and with golden bowls full of incense, which are the prayers of the saints.
Vain Repetitious prayer?
And the four living creatures, each of them with six wings, are full of eyes all round and within, and day and night they never cease to sing, “Holy, holy, holy, is the Lord God Almighty, who was and is and is to come!”
Mark 14:39 - Agony in the Garden - Withdrawing again, he prayed, saying the same thing.
Its like saying protestants repeat vain repetition when singing a song and repeating the Chorus.
What Jesus warns against is Vain repetition. Vain means empty, and we should not sing prayers or pray to God with empty prayers. We should always strive to pray and sing devoutly to our Lord Jesus Christ.
Here are more verses showing repetition.
Psalms 103, we pray, “Bless the Lord, O you his angels, you mighty ones who do his word, hearkening to the voice of his word! Bless the Lord, all his hosts, his ministers that do his will!” (Ps. 103:20-21).
And in Psalms 148 we pray, “Praise the Lord! Praise the Lord from the heavens, praise him in the heights! Praise him, all his angels, praise him, all his host!” (Ps. 148:1-2).
We hope this helps.
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