Baptism and Lord’s Supper are the oldest and most fundamental practices of the Christian Church. From the outset, the covenant has been very important for the foundations of the practice of child baptism. Today, the practice of baptizing children is called into question, because as autonomous individuals they do not have the opportunity to make their own decisions. What does this mean for the perception of baptism and the theology of baptism at a time when autonomy of the subject is paramount and the notion that one is part of a community plays much less of a role? Another question, which is being discussed to this day, is what happens when one is baptized. How is salvation mediated in the ritual? On the basis of central texts, a cross-section of the Reformed theology will be offered over the centuries.