1 Corinthians Part 6 | 1 Cor 6:12-20

After Paul urges us to not judge others or even ourselves, because God will do that, he harshly judges a member of the Corinthian church who is guilty of sexual immorality - with his step mom. Such immorality was and remains today unthinkable. Paul does not mince words over this sinful behaviour because the stakes are incredibly high. The witness of the Corinthian church is at stake. 
God made us as embodied and sexual beings, not to do with our bodies anything we want - arguably that would not be freedom at all. Rather, we are embodied for God and he is for our bodies. Our bodies matter to God, because they are constituent to his creative desire for us to love and be loved! Paul espouses an incredibly high view of sex; a vision of human flourishing wherein sex builds one life into another and foreshadows the sublime union we will have with God one day.