Evangelical.
Not apostle, as he never met Jesus; however, one could say he was the most influential missionary.
Also, one could argue he was an influential latent homosexual.
Paul.
No doubt, Paul was the most influential proponent of the Christian gospel in the first century.
Paul.
John Calvin
Saint Augustine.
The Ancient Greek and Roman civilizations.
He was most influential musician in the early year of jazz
No, he did not paint cubist art, but he inspired the cubists.
The Apostle Paul
The Ancient Greek and Roman civilizations.
he was an influential writer and thinker he was an influential writer and thinker
The comparative form of "influential" is "more influential" and the superlative form is "most influential."