Book excerpt: This first full-length theological study of sources from early medieval Wales traces common Celtic features in early Welsh religious literature. The author explores the origins of the earliest Welsh tradition in the fusion of Celtic primal religion with primitive Christianity, and traces some considerable Irish influence. These specific Celtic spiritual emphases are examined in the religious poetry of the Black Book of Carmarthen, the Book of Taliesin and the Poets of the Princes, and in prose texts such as The Food of the Soul and the Life of Beuno. Many of these Welsh texts appear here in English translation for the first time.