“I will most gladly spend and be spent for your souls” (v15). Paul loved the Corinthians believers enough to suffer for them – including the discomfort of relational conflict. The Corinthians admired the charismatic “super apostles” and looked down on Paul for his humility and his choice to labor with his hands (v11), yet he continued to teach, encourage, and correct them in the Lord. Rather than smoothing over their misunderstandings and ignoring their sinfulness, Paul brought it all into the light (v20-21).
“… all for your upbuilding, beloved” (v19). Both love and truth, even uncomfortable truth, are necessary for the healthy “upbuilding” of our souls and our relationships.