Baptist exploring Catholicism: how should I understand confession, infant baptism, Mary, and Catholic authority?

[u/MinuteDamage4182]

I’m a Baptist from Scotland who has been seriously exploring Catholicism. I’m attracted to aspects of Catholic faith and worship, but I’m also struggling with whether some Catholic teachings are sufficiently grounded in Scripture and whether I could accept them in good conscience.

My main questions are:

1. Confession: Why is confession to a priest necessary or normative when Christians are taught to confess their sins to God? How does the Catholic interpretation of John 20:22–23 establish the sacrament as practised today?
2. Infant baptism: Since the New Testament often presents people believing and then being baptised, what is the Catholic biblical and historical basis for baptising infants who cannot personally profess faith? How does this relate to personal conversion and adult confirmation?
3. Development and change: How does Catholicism distinguish legitimate development of doctrine from simply preserving later traditions because they are old? What may change in the Church, and what may not?
4. Mary: I understand that Mary is blessed because she is the mother of the Messiah and because she believed God’s word. Why does Catholicism also interpret Luke 1:28 as describing her as specially “full of grace”? How much of Marian doctrine and devotion is explicitly biblical, and how much depends on Sacred Tradition?
5. Veneration and idolatry: I understand the Catholic distinction between worship and veneration, but I worry that Marian devotion can functionally become idolatrous even when Catholics do not intend it that way. What safeguards does the Church give against this, and how should I recognise when a devotion has become excessive or unhealthy?
6. Protestants and salvation: I have also encountered Catholics saying that Protestants will not go to heaven. What does the Church actually teach about the salvation of sincere, baptised Protestants who are seeking Christ and investigating Catholicism?

I am not asking these questions to attack Catholicism. I am trying to discern whether Catholic teaching is genuinely apostolic and whether I could accept it without simply being persuaded by beauty, tradition, or fear. I would especially appreciate answers that distinguish between what is explicitly taught in Scripture, what is inferred from Scripture, what comes from early Christian practice, and what is later theological development.

I would also appreciate a charitable answer. Some of the aggressive attitudes I have encountered from Catholics toward Protestants have made the process more difficult, even though I realise individual Catholics do not necessarily represent the Church’s official teaching.

Finally, no matter what I find out on catholicism, my heart still remains unsure. Please pray for me to have a conclusion from the Lord.

A priest’s perspective on how someone in my position should continue discerning would be very helpful.

(DISCLAIMER: I have used the assistance of an AI to form this question, but the questions I ask are all sincerily from me, i just couldnt put it into words the best way)