1 Cor 5:9 strongly implies that Paul had already written a letter to the Corinthians before the one we know as 1 Corinthians, but of this letter, we have no trace. It is interesting to consider just how many letters Paul must have written during his lifetime and look at those we have in our New Testament. Why don’t we have all of them? Surely they were all of historical interest?
Christians believe that the Bible is inspired by God and that He has ensured everything we need for life and for salvation is contained within that word. We do not know why we do not have other letters written by the apostles, but the fact remains that we have all that we need. This letter shows us some of the concerns facing that church, but it also has advice and help applicable to all Christians, as the opening verses make clear.
The church in Corinth may have had problems with arrogance, richness and promiscuity, but Paul’s confidence for them is rooted in God’s character: in His grace and faithfulness (1 Cor 1:1-9). We are all sanctified by the Lord and are in the process of being made holy. Our lives may often look muddled and far from perfect, but we are secure not in our own efforts to keep and save but in God’s ability to complete the work He has started (see also Phil 1:6). We have a powerful, faithful, miracle-working God who is able to keep us strong in the faith.