“[Martin Luther’s] choice of October 31, the eve of All Saints’ Day, for posting the Theses, has also its very distinct significance. This choice was determined by something more than a desire to gain for them the publicity which that day provided. All Saints’ Day was not merely the anniversary of the consecration of the church, elaborate services on which were attended by thousands. It was also the day on which the great collection of relics accumulated oy the Elector was exhibited; and to the veneration of them and attendance on the day’s services special indulgences were attached. It was, in a word, Indulgence Day at Wittenberg; and that was the attraction which brought the crowds thither on it. Luther, we have just pointed out, had preached a sermon against indulgences on the preceding October 31. On this October 31 he posts his Theses. The coincidence is not accidental. The Theses came not at the beginning but in the middle of his attack on indulgences, and have in view, not Tetzel and his Jubilee indulgences alone, but the whole indulgence system.” — B.B. Warfield, The Ninety-Five Theses in Their Theological Significance (1917)