One sin Paul addresses is that of "fornication," which is sexual relations outside of marriage. The kind of fornication Paul talks about is a class of what our culture calls incest, which is sexual relations with someone too closely related to marry. Paul admonishes the Corinthians to quit sheltering the offending man and to expel him from the community: "Put away the wicked man from among yourselves" (American Standard Version, 5:13).
One thing Paul writes about that might be considered discussing "self" is the role of a woman's hair. While Paul insists that a woman must have her hair veiled to pray, he also asserts that a woman's hair is a special attribute to her self: "if a woman have long hair, it is a glory to her" (ASV, 11.15).
One thing that Paul talks about relating to the soul is the virtues and dangers of partaking of the Lord's Supper. He admonishes that those who partake without "discerning" their souls (evaluating the condition of their souls, i.e., having asked forgiveness as the Apostle John taught) condemn themselves to be "chastened of the Lord" for having violated the sanctity of the remembrance of the Lord's final supper before His crucifixion: "For as often as ye eat this bread, and drink the cup, ye proclaim the Lord's death till he come" (ASV, 11.26).