Naturally this skirl on the trumpet made Knox odious to Elizabeth, for to impeach her succession might cause a renewal of the wars of the Roses.

Nothing less could have happened, if a large portion of the English people had believed in the Prophet of God, John Knox.

He could predict vengeance on Mary Tudor, but could not see that, as Elizabeth would succeed, his Blast would bring inconvenience to his cause; or, seeing it, he stood to his guns.
He presently reprinted and added to his letter to Mary of Guise, arguing that civil magistrates have authority in religion, but, of course, he must mean only as far as they carry out his ideas, which are the truth.
In an "Appellation" against the condemnation of himself, in absence, by the Scottish clergy, he labours the same idea.

Moreover, "no idolater can be exempted from punishment by God's law." Now the Queen of Scotland happened to be an idolater, and every true believer, as a private individual, has a right to punish idolaters.

That right and duty are not limited to the King, or to "the chief Nobility and Estates," whom Knox addresses.