Delivered in that stronghold of German Protestantism and by a prelate of the highest standing, it was immediately printed, prefaced by three laudatory poems from different men of note, and sent forth to drive back the scientific, or, as it was called, the "godless," view of comets.

The preface shows that Dieterich was sincerely alarmed by the tendency to regard comets as natural appearances.

His text was taken from the twenty-fifth verse of the twenty-first chapter of St.
Luke: "And there shall be signs in the sun, and in the moon, and in the stars; and upon the earth distress of nations, with perplexity; the sea and the waves roaring." As to what comets are, he cites a multitude of philosophers, and, finding that they differ among themselves, he uses a form of argument not uncommon from that day to this, declaring that this difference of opinion proves that there is no solution of the problem save in revelation, and insisting that comets are "signs especially sent by the Almighty to warn the earth." An additional proof of this he finds in the forms of comets.

One, he says, took the form of a trumpet; another, of a spear; another of a goat; another, of a torch; another, of a sword; another, of an arrow; another, of a sabre; still another, of a bare arm.

From these forms of comets he infers that we may divine their purpose.