At first read this passage can appear complex and clunky. However, we should continue to make the assumption that Paul is continuing to reply to his accusers in Corinth, who have accused him of reneging on his promised visits to them: ''If he is untrustworthy with his visits, then how can we trust the things he says about God?'' they state, a truly damaging accusation. He replies that he postponed his visit to them because things had become so bad that any appearance for him would have made the situation worse rather than better, so he wisely waited.
Paul, in his defence, states here that Jesus is the 'Yes' of God; that is to say that everything God says about Himself or anything the Apostles or Prophets say about God is confirmed by the words and life of Jesus. I was told in my days involved in pastoral ministry training at a large seaside Baptist church that I should never promise anything I couldn't deliver: someone bemoaning the fact that they couldn't get transport to visit a loved one in hospital, don't offer straightaway and then discover that your diary is booked for vital events the day you offered to drive them. Go home, check that you are free and then phone and offer. God didn't promise anything which He then didn't deliver through Jesus Christ.
In his writing to defend himself, Paul states two great things:
1. It is through Jesus that we say 'Amen' to the promises of God. We often end our prayers with 'In Jesus' Name' and with the 'Amen' it means 'let it be' and is a word which expresses our confidence to God concerning the fulfillment of His promises to us. Jesus is the guarantee that our prayers will be heard and that all the great promises are true.
2. Paul brings up the deposit of the Holy Spirit in our hearts, the first instalment paid as a guarantee that the rest will follow. The kind of life we live by the help and power of the Holy Spirit is the first instalment of the life of heaven and the guarantee that the fulness of that life will some day open up to us. In the Holy Spirit's presence in our hearts, we can know for sure that one day the 'full payment' will come, not through anything that we have done, but solely through the grace of God to us.