Some here perhaps aren’t interested in hearing the Catholic defense or are closed to it, but for latecomers who missed it, I’ll re-post this by Fr. Serpa:
Dear Un,
The Church does not teach that we are redeemed by Mary. That would be heresy. It is important to realize that co-redemptrix does not mean co-equal. She co-operated in His mission of redeeming the world. He alone is the redeemer. She co-operated by the fact that the Father chose her to be the channel through which His Son entered the human race. She gave birth to Him and sustained Him through His childhood until adulthood. This is truly co-operation and this is all that is really meant by “co-redemptrix.” Because it is so easy to misunderstand this term, the Church has not made it an official title.
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Fr. Vincent Serpa, O.P.
catholic.com/library/mary_saints.asp
geocities.com/thecatholicconvert/biblecheatsheet.html
If you mediate when you pray for someone as part of God’s body/family you are a mediator. Seems logical to me. It’s also quite Biblical:
Intercessory Prayer of Saints
Rom 15:30 - join me by your prayers to God on my behalf
Col 4:3, 1Thess 5:25 - pray for us
2Thess 1:11 - we always pray for you
2Thess 3:1 - finally, brothers, pray for us
Eph 6:18-19 - making supplication for all the saints & for me
Tob 12:12 - angel presents Tobit & Sarah’s prayer to God
Ps 148 - David calls upon angels
Zech 1:12 - angel intercedes for Jerusalem
Mk 12:25, Mt 22:30 - men in heaven are as the angels
Rev 5:8 - those in heaven offer prayers of the holy ones to God
*Saints dead, what about necromancy (Dt 18:10-11)
Mk 12:26-27 - he is God of the living, not of the dead
Mk 9:4 - Jesus seen conversing with Elijah & Moses
Lk 9:31 - Elijah & Moses aware of earthly events
Rev 6:9-11 - martyrs under altar want earthly vindication
Heb 12:1 - we are surrounded by a cloud of witnesses
Lk 16:19-30 - departed rich man intercedes for brothers
Rev 20:4 - saw the souls of those who had been beheaded
Wis 3:1-6 - the souls of the just are in the hand of God
2Macc 15:7-16 - the departed Onias & Jeremiah pray for the Jews
Jas 5:16 prayers of righteous man
1 Cor. 13:12 - I shall understand fully
1 John 4: 20-21 - whoever loves God must love his brother
1 Cor 12:21 - parts of Christ’s Body cannot say to other parts, “I do not need you”.
*1Tim 2:5 - “One mediator between God and man”
1Tim 2:1-7 - offer prayers, petitions for all men
1Pet 2:5 - be a holy priesthood to offer sacrifices through Christ
Mk 10:18 - only God is good (see next)
Mt 25:23 - well done my good and faithful servant
Jn 10:11-16 - I am good shepherd; one flock I shepherd (see next)
Jn 21:15-16 - feed my lambs, tend my sheep
Eph 4:11 - He gave some as apostles…others as pastors
Heb 3:1, 7:24, 9:12-13 - Jesus eternal high priest; one sacrifice (see next)
Rev 1:6, 5:10 - He made us a kingdom of priests for God
Jesus, being both God and man is uniquely a mediator between God and man. This does not mean that other types of mediation are impossible.
Similarly, God is the creator of all, yet he allows us to be creative in many subordinate ways to give glory to God.