1 John 1:9 (BSB)

If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness.

From 1 John 1. Also in the ESV.

Commentary on 1 John 1:9

• John Calvin (Reformed), Calvin's Commentaries on 1 John 1:9: 9 If we confess He again promises to the faithful that God will be propitious to them, provided they acknowledge themselves to be sinners. It is of great moment to be fully persuaded, that when we have sinned, there is a reconciliation with God ready and prepared for us: we shall otherwise carry always a hell within us.
• Matthew Henry (Presbyterian), Matthew Henry's Complete Commentary on 1 John 1:8-10: Here, I. The apostle, having supposed that even those of this heavenly communion have yet their sin, proceeds here to justify that supposition, and this he does by showing the dreadful consequences of denying it, and that in two particulars: - 1. If we say, We have no sin, we deceive ourselves, and the truth is not in us, Jo1 1:8.
• John Gill (Reformed Baptist), Exposition of the Old and New Testaments on 1 John 1:9: If we confess our sins,.... Not to one other; for though it is our duty to confess our faults to our fellow creatures and fellow Christians which are committed against them, yet are under no obligation to confess such as are more immediately against God, and which lie between him and ourselves; or at least it is sufficient to confess and acknowledge in general what...
• Albert Barnes (Presbyterian), Barnes' New Testament Notes on 1 John 1:9: Verse 9. If we confess our sins. Pardon, in the Scriptures, always supposes that there is confession, and there is no promise that it will be imparted unless a full acknowledgment has been made. Compare ; . He is faithful. To his promises. He will do what he has assured us he will do in remitting them. And just to forgive us our sins.