What happened when Paul preached the Gospel of the Grace of God to pagans?
When Paul preached the Gospel of the Grace of God to pagans, they came out of their paganism and became believers, called Christians. He brought nothing but that Gospel to abject pagan people, and it was effective in calling them out of the unbelieving world.
Les explains that Paul's message was directed to the pagan world. He could come to abject pagan people with nothing but the Gospel of the Grace of God, and they would come out of their paganism and become believers—or, as the term is normally used, Christians. This fits God's time of calling out Gentiles from the unbelieving world. Les notes that the term Christian has lost its efficacy, since today almost anybody or anything can be called a Christian. He also identifies this message as the Gospel of Christ, the Gospel of the Grace of God, the Gospel of God, My Gospel, and the Gospel according to the revelation of the mysteries, most explicitly laid out in 1 Corinthians 15:1-4; a different message would be a perversion, not another Gospel.