Tertullian

“ The question, however, still lies before us, that some of these observances, having been commanded by God to man, have constituted this practice legally binding; some, offered by man to God, have discharged some votive obligation. Still, even a vow, when it has been accepted by God, constitutes a law for the time to come, owing to the authority of the Acceptor; for he who has given his approbation to a deed, when done, has given a mandate for its doing thenceforward. ”

“ For, while censuring that form in which the ancient economies ran their course, and at the same time drawing out of that form arguments to hurl back (upon us) which the very adversaries of the ancient economies will in their turn be able to retort, they will be bound either to reject those arguments, or else to undertake these proven duties (which they impugn) : necessarily so ”