The modern view of marriage in early Ireland has been drastically changed by recent work, but much remains to be done in this field. From an examination of books 45 and 46 of the Collectio canonum hibernensis, for example, we can deduce what were the policies and attitudes on the part of the church which must have influenced native Irish laws. The provisions concerned basically conform to the continental norm in moral matters, but as regards the legal dimension, especially where property is involved, they tend to adopt the provisions of native laws. Traces of Roman law, which Ó Corráin proposed to see in Cáin lánamna, are not obvious. Moreover, though the Hibernensis and Cáin lánamna do not differ in every respect, their dissimilar natures cannot be overlooked. In conclusion, it will be argued that the success of the church was not so total by the early eighth century as Ó Corráin maintained.