Advert, Papists, and consider how Satan has blinded you; you do manifestly lie, and do not espy the same. You do blaspheme God at every word, and can you not repent? "...O Papists! where shall you hide from the presence of the Lord? You have perverted his law; you have taken away his ordinances; you have placed up your own statutes instead of his. Woe and damnation abide you! Albeit that the apostles had made laws other than the express word commanded, what appertains that to you? Have you the Spirit of truth and knowledge in abundance as they had? Was the kirk of Christ left imperfect after the apostles' days? Bring yourselves to mind, and be ashamed of your vanity. For all men, whose eyes Satan has not blinded, may espy that neither wisdom nor authority of man may change or set up anything in the religion of God, without his own express commandment and word..."
Knox is wrong.
There is no mystery or shock to this.
I worship in the Church founded by Christ, you worship in a church founded by men like Cauvin, Knox, Machen, etc.