Faced with the reality of the contemporary world permeated by violence, from the method proposed by the theology of human action, was oriented to explain in particular the experiences of today's family, faced with the quality life of family groups that live in conflict, which threaten not only against life itself, if not against people's dignity that integrate the family group. Is thus that was analyzed, on first place, the reality of the family in all its density, radicalness and complexity as the core of the Christian community, from violent factors that conditioning it and that generate victims. In a second moment, it fundaments theologically the mercy principle as one revelator data that consolidates a proper understanding of the family and is a response that heals the ambits of domestic violence, to finally from the mercy principle, make reflexion guidelines and pastoral action that permit a new understanding of the family, transformed by the mercy principle.