The Cross of Christ changed everything!
The Apostle Paul is addressing the church in Corinth. It had become just like the city it was in with no distinction between what happened in the church and in the city. It had become polluted with every vice that the world offered. There were clear factions and divisions developing in leadership. He addresses the various issues going on and we can see his discourse in 1 Corinthians 1.
How would you begin to bring health and balance to this church? He starts by reminding them that we are called to be holy (Belonging to, derived from, or associated with Divine power; sacred.) in Jesus, that we are set apart by God (sanctified-Made holy; consecrated; set apart for sacred services), and called to fellowship (unity). He reminds them that there is One Saviour and One body and One baptism that they all were part of connecting us to Christ. Then he took them to the cross.