You seem to select only those passages that conform to your personal interpretation.
Your comment: “Baptism does not cleanse sin.”
Thus the early Church Fathers wrote in the Nicene Creed (A.D. 381), “We believe in one baptism for the forgiveness of sins.”
Cyprian of Carthage
“[T]he baptism of public witness and of blood cannot profit a heretic unto salvation, because there is no salvation outside the Church.” (Letters 72[73]:21 [A.D. 253]).
And the Catechism of the Catholic Church states: “The Lord himself affirms that baptism is necessary for salvation [John 3:5]. . . . Baptism is necessary for salvation for those to whom the Gospel has been proclaimed and who have had the possibility of asking for this sacrament [Mark 16:16]” (CCC 1257).
The Christian belief that baptism is necessary for salvation is so unshakable that even the Protestant Martin Luther affirmed the necessity of baptism. He wrote: “Baptism is no human plaything but is instituted by God himself. Moreover, it is solemnly and strictly commanded that we must be baptized or we shall not be saved
Your comment: “Forgiveness is as simple as confessing.”
Christ told the apostles to follow his example: “As the Father has sent me, even so I send you” (John 20:21). Just as the apostles were to carry Christ’s message to the whole world, so they were to carry his forgiveness: “Truly, I say to you, whatever you bind on earth shall be bound in heaven, and whatever you loose on earth shall be loosed in heaven” (Matt. 18:18).
This power was understood as coming from God: “All this is from God, who through Christ reconciled us to himself and gave us the ministry of reconciliation” (2 Cor. 5:18). Indeed, confirms Paul, “So we are ambassadors for Christ” (2 Cor. 5:20).
Your comment: “God’s grace is not based on works.”
That is correct. God’s grace is a gift to us, but one does not receive this gift if they are in the state of mortal sin.
The early Church Fathers, of course, were unanimous in teaching the reality of mortal sin. They had to embrace the doctrine of mortal sin precisely because they recognized not only the salvific power of baptism but also the damning power of certain serious sins. The Church taught that “baptism . . . now saves you” (1 Pet. 3:21; see the Catholic Answers tracts Baptismal Grace andBorn of Water and the Spirit). However, since during the persecutions some baptized people denied Christ, and since Christ taught that “whoever denies me before men, I also will deny before my Father who is in heaven” (Matt. 10:33), the Church Fathers recognized that it was possible to lose the grace of salvation after baptism.
“Watch for your life’s sake. Let not your lamps be quenched, nor your loins unloosed; but be ready, for you know not the hour in which our Lord comes. But you shall assemble together often, seeking the things which are befitting to your souls: for the whole time of your faith will not profit you, if you be not made complete in the last time” (Didache 16 [A.D. 70]).
If sanctifying grace dwells in your soul when you die, then you have the equipment you need, and you can live in heaven (though you may need to be purified first in purgatory; cf. 1 Cor. 3:12–16). If it doesn’t dwell in your soul when you die—in other words, if your soul is spiritually dead by being in the state of mortal sin (Gal. 5:19-21)— you cannot live in heaven. You then have to face an eternity of spiritual death: the utter separation of your spirit from God (Eph. 2:1, 2:5, 4:18). The worst part of this eternal separation will be that you yourself would have caused it to be
You did too.
It's not what the church fathers say about cleansing from sin that counts but what Jesus says about it.
And just now is 1 John 1:9 wrong?
God’s grace is a gift to us, but one does not receive this gift if they are in the state of mortal sin.
They HAVE to in order to be free from sin.
There is no grace needed for those who have no sin.
Romans 5:20
Now the law came in to increase the trespass, but where sin increased, grace abounded all the more,
If sanctifying grace dwells in your soul when you die, then you have the equipment you need, and you can live in heaven (though you may need to be purified first in purgatory; cf. 1 Cor. 3:12–16)
Purgatory doesn't cleanse sin.
Hebrews 9:22 Indeed, under the law almost everything is purified with blood, and without the shedding of blood there is no forgiveness of sins.
ONLY the sacrifice of Jesus, the atonement, is what cleanses from sin.
Galatians 2:15-21 We ourselves are Jews by birth and not Gentile sinners; yet we know that a person is not justified by works of the law but through faith in Jesus Christ, so we also have believed in Christ Jesus, in order to be justified by faith in Christ and not by works of the law, because by works of the law no one will be justified.
But if, in our endeavor to be justified in Christ, we too were found to be sinners, is Christ then a servant of sin? Certainly not! For if I rebuild what I tore down, I prove myself to be a transgressor. For through the law I died to the law, so that I might live to God. I have been crucified with Christ. It is no longer I who live, but Christ who lives in me. And the life I now live in the flesh I live by faith in the Son of God, who loved me and gave himself for me. I do not nullify the grace of God, for if righteousness were through the law, then Christ died for no purpose.