One further title of Jesus in the early Christian literature remains to be discussed. He is referred to as Son of God. What would this phrase mean in Jewish ears? In general the Jews regarded God as unique. The idea of a Son of God in any physical sense, such as seemed natural enough to the heathen world, would have been unthinkable to them, but they believed that God himself had used the phrase metaphorically to describe the relation between him and his chosen people. It was a moral sonship, not a physical one in the heathen sense, or a metaphysical one in the later Christian sense.
In the later literature the phrase developed on two separate lines. There was the tendency, exemplified in some of the Psalms, and still more in the Psalms of Solomon, to use the phrase "Son of God" to describe the Davidic king, but it was also used in quite a different sense in the Wisdom Literature as the description of the righteous man, and especially of the righteous man who suffered.
In Christian literature it seems tolerably clear that the history of the phrase passed through several stages. The latest, though in the end the most important for the development of doctrine, is that of metaphysical sonship, which followed upon the equation of "Son of God" with "Logos." Somewhat earlier than this, in the early chapters of Luke, and probably of Matthew, is an idea of sonship which approximates to the physical notion of the heathen world. Earlier still it was probably used as a synonym for the Davidic Messiah. The question is whether this is its meaning in the earliest passage of all,—the account given in the first chapter of Mark of the voice from heaven at the baptism which said, "Thou art my beloved Son in whom I am well pleased." It is generally held that this is a quotation from the second Psalm,[[4]] and therefore identifies Jesus with the Davidic Messiah. But is it quite so certain that it is a quotation from anything? The words of the Psalm are really quite different, "Thou art my Son" instead of "Beloved Son," and "This day have I begotten thee" instead of "in whom I am well pleased." Why should we suppose either that the voice from heaven was restricted to quoting scripture, or that it did so with quite remarkable inaccuracy? If, however, the idea be abandoned that the voice from heaven necessarily refers to the second Psalm, it becomes an open question whether Jesus himself regarded his divine sonship as the Davidic messiahship, or as that divine sonship which the Book of Wisdom ascribes to the righteous. The problem thus raised can never be settled, for the evidence is insufficient; but neither can it be dismissed, for it is implicit in the gospel itself.
The whole importance of this series of problems in the history of early Christology is often strangely mistaken. It seems to many as though the line of thought suggested above, which reduces to a vanishing point the amount of Christology traceable, in the ordinary sense of the word, to Jesus himself, is in some way a grave loss to Christianity. No doubt it is a departure from orthodoxy. But if the history of religion has any clear lesson, it is that a nearer approach to truth is always a departure from orthodoxy. Moreover, the alternative to the view stated above is to hold that Jesus did regard himself as either one or both of the two Jewish figures, the Davidic Messiah and the Son of Man described in Enoch. Both of these are part of a general view of the universe, and especially of a prognostication of the future, wholly different from our own, and quite incredible to modern minds. How do we endanger the future of Christianity by doubting that Jesus identified himself with figures central in incredible and now almost universally abandoned forms of thought?
[[1]] I have discussed the story of the gift of the Spirit at Pentecost in the Earlier Epistles of St. Paul, pp. 241 ff., and have added some critical remarks on the various forms of the tradition in the Prolegomena to Acts, i. 322 f.
[[2]] I have discussed the history of early Christian attempts to distinguish false from true prophets in "De strijd tusschen het oudste Christendom en de bedriegers" in the Theologisch Tijdschrift, xlii. 395-411.