This reflection presents two fundamental biblical categories, especially meaningful for sacramental theology: promise and covenant. They are presented in an intimate relationship to one another, as much in their content as in their realization in the course of history and revelation until their fulfillment in the new covenant. After an introduction presenting the context and the general projection of this reflection, a syntactical confirmation is presented, associated with a semantical interpretation. This biblical-theological and hermeneutical confirmation and interpretation serves as a framework for a new approach to sacramental theology in general and of some sacraments in particular. The conclusion proposes pragmatically the acquired elements in the form of suggestions for systematic theology, practical theology, liturgical and practical theology, catechetical work and spirituality.