Complex sentence: He was an advocate of the extremest form of Calvinism (Gomarism) against the Arminians; but his personal influence was good, and the city of Utrecht perpetuated his memory by giving his name to the street in which he had lived.
Split into simpler sentences: He was an advocate of a strong form of Calvinism (Gomarism) against the Arminians. His personal influence was good, and the city of Utrecht perpetuated his memory by giving his name to the street in which he had lived.