So far as we ourselves are concerned, there is only one hypothesis open to us, and it is not far to seek. It will be best if we first state it somewhat baldly, leaving obvious difficulties to be considered later. The theory is as follows:

In the first instance St. Luke wrote his Gospel, either in whole or in part, without any knowledge of the Virgin Birth. To him, as to the compiler of the Lukan Genealogy, Jesus was the son of Joseph and of Mary. St. Luke's estimate of Jesus was not less high than that of St. Paul and St. Mark, but, as was probably true in the case of each of these writers, no tradition of the Miraculous Birth had reached him. He looked upon Jesus as [pg 073] the Child of Wondrous Promise, and for his analogies he turned to the Old Testament to the stories of Isaac and of Samuel.

In contrast to earlier writers St. Luke had an excellent Birth-tradition at his disposal. According to his sources the coming and future Messianic greatness of Jesus had been divinely foretold. His birth was heralded by angelic choirs, and humble shepherds brought their meed of worship and of praise. By an insight divinely given, men like Simeon and women like Anna saw in Him the child of promise. He was to be a light for revelation to the Gentiles and the glory of His people Israel. We need not stay to look more closely into the story, which doubtless has been worked up as regards its form by the Evangelist's hand. Suffice it to say that St. Luke's picture is that of a Wondrous Birth, supernaturally foretold; not a virgin birth.70

Some time after he had penned his narrative, possibly after it had been dispatched to Theophilus, but at any rate before the Gospel gained a wider circulation, St. Luke received the tradition of the Virgin Birth. At what time and from what source the story reached him we are quite unable to say; possibly it was from some reader or readers to whom he had submitted his narrative; possibly the story travelled along some independent channel. In any case the probability is that the tradition was imparted to St. Luke by some one who claimed to possess a fuller and a better account, and whose claim the Evangelist respected and admitted. Having regard to St. Luke's standing and methods as an historian, we prefer to believe that the tradition reached him through a definite and personal channel, than to suppose that of his own initiative he freely altered a valuable source out of deference to a growing theory.

The historical value of the new information is a question we are not now considering. It is part of our theory, however, that it satisfied the mind of St. Luke; to him the Virgin Birth was historic fact. Probably the story appealed to him at once as a fitting explanation of the unique personality of Jesus. It was [pg 074] a tradition rich in doctrinal possibilities; it provoked reflection, and it answered questions.

The Evangelist saw at once that the story must find a place in his narrative. Fortunately it was not too late, and fortunately again there was a point where it could be included without entailing the necessity of rewriting cc. i, ii entirely. He had only to insert the words we have now in i. 34 f. into the address of the angel, and to add to the opening words of the Genealogy the phrase “as was supposed”, to obtain a narrative in which truths previously unknown to him found sufficient statement. If we can suppose that the adaptation of what he had previously written was not drastic enough, we obtain a hypothesis which at least does justice to every result we have yet secured.

The view that Lk. i. 34 f. is an interpolation made by St. Luke himself was put forward by Zimmermann in Studien und Kritiken (p. 273 f.) in 1903. His treatment (cf. Moffatt, INT., p. 269 n.) differs in several respects from that outlined above. Zimmermann posits an Aramaic Jewish-Christian source which described a natural birth, and suggests that it was in the course of translating this document that St. Luke added i. 34 f. The Evangelist is also credited with having altered i. 27 and ii. 5, so as to describe Mary as betrothed to Joseph. Zimmermann also explains ii. 22 (a?t??) as a mistranslation, and ascribes to St. Luke the parenthesis of ii. 35 a, and the chronology of iii. 1-2, which he holds is inaccurate.

According to this hypothesis St. Luke must have been acquainted with the Virgin Birth before he began to translate the supposed Aramaic document. This view is encumbered with difficulty; for, if Zimmermann is right, we should certainly expect a much more drastic editing of the document than can be shown. The extent to which this difficulty appears in the case of our own theory is one for which we think that justification can be given.71 In the case of Zimmermann's hypothesis the obstacle is too great. On this view we cannot understand how the Evangelist allowed himself to write down those expressions which are incompatible with the Miraculous Conception.72

The view we have preferred agrees with that of Zimmermann [pg 075] in positing a source or sources which described a natural birth. It differs from it in denying that the Evangelist knew of the Virgin Birth at the time when he made use of those sources. We prefer to think that it was after cc. i, ii had attained what is substantially its present form in Greek, that St. Luke came to hear of the Virgin Birth, and that it was then that he inserted i. 34 f. This supposition includes the positive advantages of Zimmermann's theory, and it agrees better with the existing literary phenomena of Lk. i, ii.73