In Paul’s day, and still today, there were those who saw “ministry” as a quick gig, an easy way to make money (2:17). Paul’s ministry credentials were the lives changed by the power of the Holy Spirit. The fact that many violently rejected his ministry was not incongruous to his credibility, but affirming of it. Jesus had also been rejected.
Paul wrote, “We have this treasure in vessels of clay, that the surpassing greatness of the power will be of God... we are afflicted in every way,...constantly delivered over to death for Jesus’ sake.” But he also said, “... momentary, light suffering is producing for us an eternal weight of glory!” True spiritual life must be the product of the Holy Spirit. All other is imitation.