I am just going to have to go with what Jesus taught in the Lord’s Prayer. It is perfect because he is perfect.
He showed us how to pray, and asking forgiveness was part of that, along with forgiving others.
I just don’t see anything that convinces me that one should confess to a priest, rather than directly to God.
John 20: 21-23 is pretty clear to me.
Jesus said to them again, “Peace be with you. As the Father has sent me, so I send you.” And when he had said this, he breathed on them and said to them, “Receive the holy Spirit. Whose sins you forgive are forgiven them, and whose sins you retain are retained.”
And the 1 John 1:9 verse also negates purgatory to me.
I think it supports it rather than negates it. It says we will be cleansed, it doesn’t say when or how. Purgation is cleansing.
I also think 1 Corinthians 3:15 points to this, “He will suffer loss, though he himself will be saved, but only as through fire”
Complicated Catholic theology keeps bumping in to simple Biblical truth in some places to me.
I think “complicated” is an overstatement. I have never found anything to be complicated. I converted at age 25.
Edited to add:
I think the most complicated thing for some non-Catholics is to get over the Sola Scriptura hump. I think that if you study carefully how the New Testament church actually operated and functioned from the beginning you can get there. Especially looking at the church of around 100-150 AD when the Apostles had died and the second and third generation bishops were charged with leading the church-- Irenaus, Polycarp, Clement, and others.
It was not based on a book. It was based on preaching, teaching, and handing on the traditions and the celebration of the Mass orally. Some of it was written down, as we are told by St Paul himself: hold fast to the traditions you have been given, either in writing or orally.