1 John 1:9: If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness.
I am glad that it is not just some unrighteousness. I am glad it is not just past unrighteousness.
Proverbs 28:13: He that covereth his sins shall not prosper: but whoso confesseth and forsaketh them shall have mercy.
All unrighteousness includes past, present and future unrighteousness. If we confess some sins but cover others, His forgiveness is not promised. Neither is His forgiveness promised if we confess our sins but do not intend to forsake them. He is gracious in His cleansing of past unrighteousness. But we have part in cleansing ourselves from present and future unrighteousness. We must do all that is in our power to avoid temptation and resist it, now and in the future. He will help us do that today and for the rest of our lives. When we fail he promises to forgive again. We should depend upon His mercy but we should not presume upon it by stepping into temptation or yielding to it on purpose. Unrighteousness is a habit we can break with His help. We can ask for His help and when He offers it, take advantage of it.
Matthew 6:13a: And lead us not into temptation, but deliver us from evil: . . .
1 Corinthians 10:13: There hath no temptation taken you but such as is common to man: but God is faithful, who will not suffer you to be tempted above that ye are able; but will with the temptation also make a way to escape, that ye may be able to bear it.