"Assumptus homo" is the name given to the first of the three main trends Peter Lombard identified in theological attempts to explain the incarnation. It is not a particular theory, but a line of thought that can be traced back to the Patristic period when many of the Fathers described the Incarnation in terms of the Word assuming humanity in its entirety. It can also claim to find roots in such scriptures as the baptismal account in Mark and Peter's sermon in Acts of the Apostles 2, both of which could be read to say that an already existing human being, Jesus of Nazareth, has been made Lord and Messiah either at the baptism or the resurrection.
Christologies of this sort seek to protect the full humanity of Christ. However, they do so by means that tend toward such heresies as adoptionism and nestorianism. The term used, assumptus homo, could be read as "the man the Word assumed to himself," suggesting the existence of an already-existing man. Further, some medieval thinkers assumed that the full humanity of Christ, composed of body and soul, must constitute a human person. They lacked a more technically sophisticated language that would enable them to hold the full humanity of Christ without claiming that it must be a human person. This line of thought was never condemned, but Thomas, Scotus and other scholastics express serious reservations about it.
Recent theology has seen many attempts to recover the full humanity of Christ, including a fully human psychological autonomy. Some have returned to the assumptus homo line of thought to accomplish this. D. M. de Basly (d. 1937) claimed that his view was in the tradition of the Antioch school and of Scotus. L. Seiller went so far as to say that Christ in His manhood was a "somebody" and this opinion was condemned by the Holy Office [Acta Apostolicae Sedis 43 (1951) 561]. The encyclical Sempiternus rex (H. Denzinger, Enchiridion symbolorum, ed. A. Schönmetzer, 3905) does not reject the term assumptus homo, but says it has to be used with discernment as it can easily lead to adoptionism. Other theologians simply discuss the full humanity of Christ without getting involved in the technical scholastic issues concerning the term "person." Karl Rahner claimed that the word "person" has undergone great shifts in the modern period and that any future Christology must begin by rethinking the terminology.
Bibliography: k. rahner, "Current Problems in Christology," Theological Investigations 1 (Baltimore 1961), 149–200; "On the Theology of the Incarnation," Theological Investigations 4 (Baltimore 1964), 105–20. j. pelikan, The Christian Tradition: A History of the Development of Doctrine, v. 1 (Chicago 1971), 175–76. w. kasper, Jesus the Christ (New York 1976), 238–45. w. pannenberg, Jesus, God and Man (Philadelphia 1968), 295–96.
[m. e. williams/
m. b. raschko]