PaedoBaptism is hard to understand for a Baptist because it is not an argument solely from the New Testament. Although there are NT verses that make no sense from a believers only baptism viewpoint (See Col. 2:11-12) It’s easy to get bogged down with all the complex and varying views on covenant theology, but the idea of baptizing believers and their children is simple. I think my personal confusion with the idea of believer’s only baptism was rooted in the idea that only New Testament believers are born again by the Holy Spirit which started in time in the New Testament era at Pentecost/great commission. So Baptism to me was a visible sign of an new inward reality. But, if you see that the old and New Testament church is one body of true regenerate believers, and all Israel has to be born again, as Jesus told Israel’s teacher Nicodemus, then you wouldn’t have an issue with infants being circumcised or baptized before a profession of faith since both are signs of God’s promise and not a sure sign of our personal decision in salvation.