Complex sentence: The early "Didascalion" was an elementary, encyclopedic approach to God and Christ, in which Hugh avoided controversial subjects and focused on what he took to be the core beliefs of Catholicism.
Split into simpler sentences: The early "Didascalion" was an elementary, encyclopedic approach to God and Christ. There Hugh purposefully avoided controversial subjects and focused on what he took to be the core beliefs of Catholicism.