I'm going to do my next study of on 1 Corinthians. Why? Not really sure. I did learn something about skipping over the greeting at the beginning of Paul's books, because there is even depth there. 1 Corinthians starts out with Paul's introduction of himself as "called by the will of God to be an apostle of Christ Jesus".
For some reason, this is as far as I got today. "Called by the will of God" struck me because we use the word "called" often without thinking about the will of God. Paul's understanding of grace was so far beyond mine. He recognized he was called because it was the will of God. This understanding should lead us to a deeper commitment to live lives that please God.