Section — Wouters, Manual of Moral Theology
§ 1. On a Promise Made to the Partner
84.
I. Effect of the impediment. One who is bound by a promise not to use marriage: if he has obligated himself from fidelity, exacts the debt lawfully but unlawfully; if he has obligated himself from justice, he exacts the debt neither lawfully nor licitly. He can nevertheless ask amicably, because the partner is able to remit the promise. Thus theoretically, because in practice a promise of this sort will easily be invalid, or at least will not be able to be urged.
85.
II. Cessation of the impediment. A promise made by one party can be remitted by the partner; one made by both can be removed by the consent of both.