The present book has developed out of a short pamphlet entitled Hat die alteste Christenheit die Kindertaufe geubt? (Did the primitive Church practise infant baptism?). It does not attempt to do more than lay before the reader the historical material relating to the history of infant baptism in the first four centuries in as concrete and sober a manner as possible. This material has increased in an unexpected manner in the last decades. In this context I refer principally to the enrichment of our knowledge about proselyte baptism, the studies made of early Christian epitaphs, the ascription of the so-called Egyptian Church Order to Hippolytus, and the ascription to Asterius of some homilies on the Psalms which previously had wrongly been attributed to Chrysostom. Although much remains obscure, especially in the matter of its first beginnings, it may still be said that the early history of infant baptism is much more clearly defined today than in any previous age.