Paul claimed that his message was true, his motives were pure, and his methods were straightforward. He had behaved in Thessalonica as he had elsewhere, as a faithful servant of God. He did not preach for the approval of men but God, who scrutinizes motives. [source][source][source]
"Few temptations assail the preacher more strongly than this one to please men, even if God is not pleased, though with the dim hope that God will after all condone or overlook. Nothing but experience will convince some preachers how fickle is popular favour and how often it is at the cost of failure to please God." [1][source]