Complex sentence: Having taken holy orders in 1630, and joined the Society of Jesus in 1638, he successively taught philosophy and theology in the Collegium Romanum; as professor of theology he was a member of the congregation appointed by Innocent X to investigate the Jansenist heresy.
Split into simpler sentences: Having taken holy orders in 1630, and joined the Society of Jesus in 1638, he successively taught philosophy and theology in the Collegium Romanum. As professor of theology he was a member of the congregation appointed by Innocent X to investigate the Jansenist heresy.