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Yes, Christians throughout history have prayed to the Blessed Mother and the saints and angels for help and intercession.
In the same way that I may ask you, a brother or sister in Christ, “Please pray for me. . .” I ask Mary to pray for me to her Son and because of her special relationship with Him, we believe that her prayers are powerful.
We go to Mary for help and intercession, not INSTEAD of going to Christ, but BECAUSE of Him.
We know, through Scripture and the Church, that Jesus is the one Mediator between God and man (1 Tim. 2:5). Jesus Christ, through His Life, Death, and Resurrection, makes it possible for us to have fellowship with our heavenly Father and with all the saints and angels. This Mediator of the New Covenant, our Lord Jesus Christ, has flung open the gates of heaven that we may experience grace and fellowship as members of God’s family.
We know, too, that Jesus is the one great high priest (Heb.8:1), yet God calls all Christians a “priestly people” and invites us to share in His priesthood (1 Peter 2:9).
In the very same way, we know that God alone accomplishes and provides everything that we need, but in the fullness of His design he has chosen to include us, his creatures, in his work of mediation by allowing and enabling us to pray to God for each other. This is how we understand St. Peter’s instruction: “As generous distributors of God’s manifold grace, put your gifts at the service of one another, each in the measure he has received” (2 Peter 4:10).
This is what we believe Mary does. That’s what we believe the saints do. Scripture tells us that we are “surrounded by this cloud of witnesses” which are those who have gone before us in the faith (Hebrews 11 and 12). These witnesses are examples to us and are eternal brothers and sisters through Christ, we are “fellow citizens with the saints and members of the household of God” (Eph 2:19-21). As fellows, they are our friends in Christ, and we turn to them just as we turn to each other for help and intercession.
We are told in Scripture that we are to “pray for one another that you may find healing. For the fervent prayer of a holy man is powerful indeed” (James 5:16). The saints and the Blessed Mother are closer to Christ than we are. They are with Him in heaven, glorified, saved, and praying for us as we run this race that they have already completed.