2 Cor 7:1, 9-10 Since we have these promises, dear friends, let us purify ourselves from everything that contaminates body and spirit, perfecting holiness out of reverence for God...yet now I am happy, not because you were made sorry, but because your sorrow led you to repentance. For you became sorrowful as God intended and so were not harmed in any way by us. Godly sorrow brings repentance that leads to salvation and leaves no regret, but worldly sorrow brings death.
There is a teaching going around that there is no need to confess our sins anymore since Christ has died for us once and for all. This is like saying we don't need to ask God for any blessing since God has "blessed with every spiritual blessing in Christ" (Eph 1:3).
I think Paul's exhortation to "purify ourselves" from everything that contaminates body and spirit is a strong biblical injunction to confess our sins. In 1 John 1:9, we read that the only way to "purify ourselves" is through confession of our sins: "If we confess our sins, God is faithful and just and will forgive us and purify us from all unrighteousness." In fact, when Jesus says, "Blessed are the pure in heart", he uses the word katharos, which implies "pure as being cleansed". And it is quite clear that keeping ourselves "pure" is not about staying "sinless" but staying "cleansed" by removing daily defilement of body & spirit caused by our careless thought, word & deed (wilful or otherwise). Thank God that through His grace, we have access to forgiveness (and therefore cleansing) through confession.
2 Cor 7:15-16 And (Titus') affection for you is all the greater when he remembers that you were all obedient, receiving him with fear and trembling. I am glad I can have complete confidence in you.
The characteristic of obedience is what makes Paul proud about the Corinthian believers. Though they have fallen, they picked up quickly once they were told about their wrongdoings. They quickly repented and confessed their sins and were therefore purified as a church. We need to be believers who respect spiritual authority and receive their teaching with "fear and trembling" rather than a "why-should-I-listen-to-you?" attitude.
2 Cor 8:1-2, 6-7 And now, brothers, we want you to know about the grace that God has given the Macedonian churches. Out of the most severe trial, their overflowing joy and their extreme poverty welled up in rich generosity...So we urged Titus, since he had earlier made a beginning, to bring also to completion this act of grace on your part. But just as you excel in everything — in faith, in speech, in knowledge, in complete earnestness and in your love for us-see that you also excel in this grace of giving.
Paul speaks of the "grace" of giving rather than the "law" of giving (tithe). He refers to the "grace that God has given the Macedonian churches." New Testament giving is never under compulsion (whatever the percentage we have decided to pledge) because it is never a compliance to a law but an overflow of the grace of God working within us. If we give grudgingly, it won't be an act of grace. An act of grace is always free and joyful. May God grant us this "grace of giving" that he has granted the Macedonian churches. (Incidentally, don't for a moment think that God usually gives this grace to the rich, for the Macedonian churches were extremely poor.)
Father, we thank You for the examples of the Corinthian and Macedonian churches. We thank You for the obedience of the Corinthian church to authority and teaching and for the generosity of the Macedonian churches for You have granted them different graces--one is the grace of repentance and the other the grace of giving. May we learn from their examples. Through Christ our Lord. Amen.