Is praying the rosary biblical?Historically, the rosary was intended by the Roman Catholic Church as an affordable way to teach and recite prayers. During medieval times, there were many faithful who could not afford a Psalter (a written collection of the Psalms) or who were entirely illiterate. Traveling priests would use strings of beads to help people memorize and recite Scripture (https://www.catholiccompany.com/content/information-about-the-rosary). It grew from there to encompass prayers associated with the life of Jesus. As a tool to teach prayer and meditation, the original intentions and uses of the rosary were in line with Scripture's emphasis on both.
However, it is in the "Hail Mary" and "holy Queen" sections of the rosary, as well as the promised expectations of the rote prayers, that we do not find any scriptural basis. In fact, praying to Mary is directly against the Bible's teaching. Our prayer should only ever be directed to God (Hebrews 4:14–16; 7:25; 10:19–22; Romans 8:26–27). Treating prayer as a formula that leads to our intended end or produces a specific benefit if said the correct way the correct number of times is a complete misunderstanding of the nature and purpose of prayer (Matthew 6:5–13; 1 John 5:14–15).
The Hail Mary prayer is based on Luke 1:26–33, when the angel Gabriel appeared to tell Mary that she would become the mother of Jesus, the Savior. Gabriel greets Mary by saying, "Greetings, O favored one, the Lord is with you!" (Luke 1:28). The word "greetings" (chairo in Greek) can also be translated as "hail" or "ave," which has the weight of formality and honor usually reserved for kings. Certain translations of this interaction render it, "Hail Mary, full of grace," which is the basis of the rosary prayer.
There is no argument that Mary was indeed a very special person in God's plan for humanity's redemption. The point at which we must distinguish what is and is not scriptural is attributing to Mary any kind of ability to intercede on our behalf or to see her as one outside the need of the saving grace only available through Jesus Christ. The emphasis on praying to Mary through the rosary is based on a belief that she was somehow sinless and so close to God as to be one who could intercede for others. There is nowhere in the Bible that we see this. In fact, Scripture is very clear that we have only one mediator and that is Jesus Christ (1 Timothy 2:5).
Likewise, praying the rosary has been associated with promises like removal of sin, special graces and protection, receiving anything they pray for, special standings in heaven, and so on. Again, there is no biblical basis for these promises associated with a recitation of certain prayers in a certain order a certain number of times (Matthew 6:7–8). The removal of sin is only by grace through faith in Jesus Christ (Ephesians 2:4–9). All those who believe are promised the same spiritual protection and grace, and nowhere are we promised to have our prayers answered exactly how we would like them to be answered. All is grace in Christ Jesus.
Our example for prayer comes from Jesus Himself. Though Jesus' model of prayer, often referred to as the Lord's Prayer (Matthew 6:5–15), is included in the praying of the rosary, as well as used by rote in Protestant churches, Jesus modeled an intimate prayer life with God that was not by memorization but through honest, fervent prayers like the one in the garden of Gethsemane (Luke 22:39–46). It is not wrong to pray the prayers we see in Scripture or other biblically-sound, pre-written prayers; but we are to pray with our minds and our hearts (1 Corinthians 14:15; John 4:24), actually communicating with our heavenly Father, not merely reciting words. This is the type of prayer life God wants for us in our relationship with Him (Philippians 4:8; 1 Thessalonians 5:17; Hebrews 4:14–16; 10:19–23). All the spiritual blessings and inheritance of faith we enjoy are because of and through Jesus Christ, the only Savior (Ephesians 1:3–14).
What is the Lord's Prayer? How is the Lord's Prayer a model for our prayers?
Is praying Scripture effective?
Is it wrong to pray written prayers?
What can be learned from the prayers Jesus prayed?
What is the importance of daily prayer in the life of a Christian?
Truth about Prayer