Complex sentence: Ceolfrid, according to Bede, accompanied Benedict on at least one of his journeys to Rome and acquired his master's love of books and continued to develop the library at Wearmouth which amounted to 300 volumes making it the largest in Anglo-Saxon England.
Split into simpler sentences: Ceolfrid, according to Bede, accompanied Benedict on at least one of his journeys to Rome. Sharing his master's love of books, Ceoldrid continued to develop the library at Wearmouth, which amounted to 300 volumes--the largest in Anglo-Saxon England.