Why could Christianity have never gotten off the ground without God's miraculous power?
Christianity faced impossible odds because converts were steeped in idolatry or Judaism, and Paul rarely stayed long in one place—often only weeks—while new believers came fresh out of paganism. Human effort could not sustain them or spread the faith through the Roman Empire; only God's miraculous working power enabled it to survive and grow.
Les teaches that Christianity would never have gotten off the ground apart from God's miraculous working power. The odds were impossible: the people were steeped in idolatry, except the Jewish element, and they were just as steeped in Judaism. Paul wasn't in any one place that long. The Jerusalem church could prosper to a degree because the apostles stayed year in and year out among the Jews in Israel. But wherever Paul established a church, it was often only a week or two—Antioch about a year and a half, Thessalonica only a couple of weeks. New believers fresh out of paganism could not have made it on their own. Les says he cannot understand it except that it was the miraculous power of God that caused Christianity to take off and start permeating the whole Roman Empire.