Hence is derived the following rule. Where not merely the particular nature and manner of an occurrence is critically suspicious, its external circumstances represented as miraculous and the like; but where likewise the essential substance and groundwork is either inconceivable in itself, or is in striking harmony with some Messianic idea of the Jews of that age, then not the particular alleged course and mode of the transaction only, but the entire occurrence must be regarded as unhistorical. Where on the contrary, the form only, and not the general contents of the narration, exhibits the characteristics of the unhistorical, it is at least possible to suppose a kernel of historical fact; although we can never confidently decide whether this kernel of fact actually exists, or in what it consists; unless, indeed, it be discoverable from other sources. In legendary narratives, or narratives embellished by the writer, it is less difficult,—by divesting them of all that betrays itself as fictitious imagery, exaggeration, etc.—by endeavouring to abstract from them every extraneous adjunct and to fill up every hiatus—to succeed, proximately at least, in separating the historical groundwork. The boundary line, however, between the historical and the unhistorical, in records, in which as in our Gospels this latter element is incorporated, will ever remain fluctuating and unsusceptible of precise attainment. Least of all can it be expected that the first comprehensive attempt to treat these records from a critical point of view should be successful in drawing a sharply defined line of demarcation. In the obscurity which criticism has produced, by the extinction of all lights hitherto held historical, the eye must accustom itself by degrees to discriminate objects with precision; and at all events the author of this work, wishes especially to guard himself in those places where he declares he knows not what happened, from the imputation of asserting that he knows that nothing happened. FIRST PART. HISTORY OF THE BIRTH AND CHILDHOOD OF JESUS. CHAPTER I. ANNUNCIATION AND BIRTH OF JOHN THE BAPTIST. § 17. ACCOUNT GIVEN BY LUKE. [104] IMMEDIATE, SUPERNATURAL CHARACTER OF THE REPRESENTATION.