prior to that moment God could not strictly be said to have had a Son, while after it the term 'Father', which for earlier theologians generally connoted God as author of reality, began to acquire the specialized meaning of Father of the Son." As regards the subjects of subordination of the Son to the Father, the New Catholic Encyclopedia has commented: "In not a few areas of theology, Tertullian’s views are, of course, completely unacceptable. Thus, for example, his teaching on the Trinity reveals a subordination of Son to Father that in the later crass form of Arianism the Church rejected as heretical." Though he did not fully state the doctrine of the immanence of the Trinity, according to B. B. Warfield, he went a long distance in the way of approach to it. Apostolicity Tertullian was a defender of the necessity of apostolicity. In his Prescription Against Heretics, he explicitly challenges heretics to produce evidence of the apostolic succession of their communities. Eucharist Unlike many early Christian writers, Tertullian along with Clement of Alexandria used the word "figure" and "symbol" to define the Eucharist, Tertullian in his book Against Marcion implied that: "this is my body" should be interpreted as "a figure of my body". While others have also suggested that Tertullian believed in a spiritual presence in the Eucharist. Baptism Tertullian advises the postponement of baptism of little children and the unmarried, he mentions that it was customary to baptise infants, with sponsors speaking on their behalf. He argued that an infant ran the risk of growing up and then falling into sin, which could cause them to lose their salvation, if they were baptized as infants. Contrary to early Syrian baptismal doctrine and practice, Tertullian describes baptism as a cleansing and preparation process which precedes the reception of the Holy Spirit in post-baptismal anointing (De Baptismo 6). De Baptismo includes the earliest known mention of a prayer for the consecration of the waters of baptism. This invocation may suggest a change in practice from baptizing in living (or running) water, where the Spirit was believed to be present, to baptizing in still water. Tertullian had an ex opere operato view of the baptism, thus the efficiency of baptism was not dependent upon the faith of the receiver. He also believed that in an emergency, the laity can give the baptism. The Church Tertullian interpreted that in Matthew