The world transforming message that Paul was committed to preaching was the news that God is for us, no longer counting our sins against us! When you read through the Bible, it is very interesting how God moves. It may be understood that God is developing and adapting with the times and the decisions of His people Israel: it could also be seen as God revealing more of Himself until the full revelation of Jesus Christ. Remember His words: ''When you have seen me, you have seen my Father!'' The Bible speaks of God as having human emotions- disappointment, anger, joy, peace, jealousy, mercy, patience and so on-but maybe it is rather that humankind, made in God's image, display His characteristics and sometimes- such as with anger and jealousy- in a fallen way?
Paul had lived his life-even before becoming a Christian- with the judgement seat of God in mind. The difference being that, now he loved God as well as feared Him and he couldn't wait to meet Him. As an aside, remember that the Fear of the Lord should not be the sort which leads to trembling, shaking and grovelling: no, the fear of the Lord is to remind you that there are boundaries to your freedom, that by doing certain things or not doing other things, you may break the heart of the Holy Spirit: it is what keeps even a thoughtless man from desecrating a holy place. I've been reading through 1 and 2 Kings in recent weeks and it is interesting that, although Judah-towards the end of its pre-Babylonian exile existence-is attacked and beaten time and time again by foreign nations, there still remains certain treasures which it can give as a ransom to free itself and nearly all of this comes from the Temple. The victorious armies generally would not go into the sacred space of the God!
Paul continues here to try to persuade others of his own sincerity. He has no doubt that in the sight of God his hands are clean and his motives pure, but his enemies have caused there to be suspicion and he wishes to demonstrate his sincerity to those in Corinth who remain his friends. A preacher's message will always be heard in the context of their character and can only be effective if it is given from a pure heart.