The various denominations and religions are increasingly coming into contact with one another in today's world. How can peaceful coexistence be achieved in the future? The mutual interactions are particularly pronounced in marriages between individuals of different religious affiliations. With the new marriage process regulation Dignitas Connubii, the Catholic Church is presenting norms for the first time that address the related legal issues. The study explains these new norms for application in legal practice, while also placing them in a broader legal and theological context. It critically examines them and outlines perspectives for the future to promote peaceful coexistence among denominations and religions.