BJ, are you saying that in Christianity the subject of sin is not important?
No, not at all.
Just have faith in Christ, and though you keep sinning, you are justified? To me that is a weird kind of faith. Aren't we suppose to love Jesus with all our hearts, mind and body, and love our neighbor? What do you mean by faith.
Our chief article says it all, and it has references, but I've added some comments for context at the bottom of the post.
Article I: The First and Chief Article
"1 That Jesus Christ, our God and Lord, died for our sins, and was raised again for our justification, Rom. 4:25
2
And He alone is the Lamb of God which taketh away the sins of the world,
John 1:29; and God has laid upon Him the iniquities of us all,
Is. 53:6.
3 Likewise: All have sinned and are justified without merit [freely, and without their own works or merits] by His grace, through the redemption that is in Christ Jesus, in His blood, Rom. 3:23f
4 Now, since it is necessary to believe this, and it cannot be otherwise acquired or apprehended by any work, law, or merit, it is clear and certain that this faith alone justifies us as St. Paul says, Rom. 3:28: For we conclude that a man is justified by faith, without the deeds of the Law. Likewise 3:26: That He might be just, and the Justifier of him which believeth in Christ.
5 Of this article nothing can be yielded or surrendered [nor can anything be granted or permitted contrary to the same], even though heaven and earth, and whatever will not abide, should sink to ruin. For there is none other name under heaven, given among men whereby we must be saved, says Peter, Acts 4:12. And with His stripes we are healed, Is. 53:5. And upon this article all things depend which we teach and practice in opposition to the Pope, the devil, and the [whole] world. Therefore, we must be sure concerning this doctrine, and not doubt; for otherwise all is lost, and the Pope and devil and all things gain the victory and suit over us."
The person and work of Christ for us, which can only be received through faith, is greater than the sins of the world. Consequently, we are received by God as justified unto eternal through faith in Him.
The answer to your question of aren't we supposed to love Jesus with all our hearts, mind, etc., and our neighbor as ourself is an absolute yes. But since the renewal in this life is not complete or perfect we don't do that always or perfectly.
Christians are in the same boat as the publican, the sinner in the parable of Luke 18, who pled the sacrifice, be
propitious to me
the sinner, and went home justified.
"And the tax-gatherer, having stood afar off, would not even the eyes lift up to the heaven, but was smiting on his breast, saying, God be propitious to me -- the sinner!" Luke 18:13, YLT
https://www.biblegateway.com/passage/?search=Luke+18:13&version=YLT
Just as the publican in the parable, Christians implore God's mercy based upon the sacrifice, Christ, rather than upon our own merits. So Christians confess their sin and God is faithful and just to forgive us our sins, per 1 John 1:8-10.