Twenty years ago it was possible to regard the Synoptic Problem as virtually solved. There might still be difference of opinion on a number of details, but the main conclusions seemed to be unassailable. The sources of the three gospels, like those of the Nile, had been hidden in mystery, and the discovery of them was justly hailed as the chief triumph of nineteenth-century scholarship.

For some time it has been apparent that the rejoicings were premature. Those matters of detail which had yet to be settled have turned out to be serious, and we are now realizing, with something of a shock, that the Synoptic Problem is still with us. Instead of reaching a solution we have only come in sight of the real difficulties. If the confidence of twenty years ago is ever regained it will only be after another long spell of patient labor.

We certainly owe much to the great scholars of the last century, though their claim to discovery has been found wanting. They gave us the clues which we have still to follow. The materials they collected and the observations they made will always be valuable. Their theory itself, although it calls for drastic revision, will continue, in some essential points, to stand. It will remain certain that Mark is the earliest of our gospels and has been used by the other evangelists. It seems equally impossible to doubt that along with Mark there was another source, now lost, on which Matthew and Luke must have drawn for their record of Jesus' teaching. These results, however they may be qualified, must always form the starting-point for critical investigation. But we now recognize that the older scholars conceived of their task too narrowly. The problem before them was far more intricate than they supposed, and has to be solved not merely by comparing the editorial methods of the several evangelists but by a deeper analysis, affecting the substance as well as the formal structure of the gospels.