But he put his hesitation behind him as a suggestion of Satan.
Knox now associated with Lord Erskine, then Governor of Edinburgh Castle, the central strength of Scotland; with Lord Lorne, soon to be Earl of Argyll (a "Christian," but not a remarkably consistent walker), with "Lord James," the natural brother of Queen Mary (whose conscience, as we saw, permitted him to draw the benefices of the Abbacy of St.Andrews, of Pittenweem, and of an abbey in France, without doing any duties), and with many redoubtable lairds of the Lothians, Ayrshire, and Forfarshire.
He also preached for ten days in the town house, at Edinburgh, of the Bishop of Dunkeld.

On May 15, 1556, he was summoned to appear in the church of the Black Friars.

As he was backed by Erskine of Dun, and other gentlemen, according to the Scottish custom when legal proceedings were afoot, no steps were taken against him, the clergy probably dreading Knox's defenders, as Bothwell later, in similar circumstances, dreaded the assemblage under the Earl of Moray; as Lennox shrank from facing the supporters of Bothwell, and Moray from encountering the spears of Lethington's allies.

It was usual to overawe the administrators of justice by these gatherings of supporters, perhaps a survival of the old "compurgators." This, in fact, was "part of the obligation of our Scottish kyndness," and the divided ecclesiastical and civil powers shrank from a conflict.
Glencairn and the Earl Marischal, in the circumstances, advised Knox to write a letter to Mary of Guise, "something that might move her to hear the Word of God," that is, to hear Knox preach.

This letter, as it then stood, was printed in a little black-letter volume, probably of 1556.
Knox addresses the Regent and Queen Mother as "her humble subject." The document has an interest almost pathetic, and throws light on the whole character of the great Reformer.