Calvin, it is thought, collaborated with him in the writing of it. Immediately after the sermon Cop and Calvin were forced to flee Paris.
Here is part of what Cop preached that day:
Why then do we conceal the truth rather than speak it out boldly? Is it right to please men rather than God, to fear those who can destroy the body but not the soul?--William Bouwsma, John Calvin: A Sixteenth Century Portrait (Oxford University Press, 1988), 15-16
O the ingratitude of mankind, which will not bear the slightest affliction in the name of him who died for the sins of all, him whose blood has freed us from eternal death and the shackles of Satan! The world and the wicked are wont to label as heretics, imposters, seducers and evil-speakers those who strive purely and sincerely to penetrate the minds of believers with the Gospel. . . .
But happy and blessed are they who endure all this with composure, giving thanks to God in the midst of affliction and bravely bearing calamities. . . .
Onward, then, oh Christian men. With our every muscle let us strive to attain this great bliss.