Christians are "clean" in the sense that God has cleansed them from sin. They do not need to be concerned with being clean according to the law of Moses. Ungodly living can still make a Christian unclean. (See: [[rc://en/tw/dict/bible/kt/clean]] and [[rc://en/tw/dict/bible/kt/lawofmoses]])
The words "sad" and "sorrow" in this chapter indicate that the Corinthians were upset to the point of repenting. (See: [[rc://en/tw/dict/bible/kt/repent]])
This chapter discusses in detail a previous situation. We can figure out some aspects of this situation from the information in this chapter. But it is best not to include this type of implicit information in a translation. (See: [[rc://en/ta/man/translate/figs-explicit]])