Complex sentence: He made attacks on the use of images, relics, and crosses, he opposed pilgrimages to obtain absolution, and he had little regard for the authority of the pope due to his belief that all bishops were equal.
Split into simpler sentences: He made attacks on the use of images, relics, and crosses. He opposed pilgrimages to obtain absolution and he had little regard for the authority of the Pope, teaching that all bishops were equal.