The Capitular Vicar of Aix had ordered the priests to celebrate a solemn Mass of Thanksgiving on the anniversary of the July Revolution of July 1830 (“the three glorious days”). Having suffered the persecution of the Church by the government brought in by that revolution, Eugene was outraged! He congratulated Father Courtès for having refused to celebrate.
I approve your attitude of reserve. It is a difficult situation; but with coolness and calculation you will win through in spite of everything, but you must be careful never to sacrifice principles.
Thus it would have been necessary to run the risk of seeing the church closed rather than sing a High Mass in thanksgiving for one of the greatest crimes committed since the world began, whose immediate consequences have been to throw Europe and the entire world into commotion
It would have been an evil act, a sin, a huge scandal, a sacrilege, a profanation, a monstrosity. So I am not surprised that the clergy of Aix did not heed this unjust command, as you are not bound to obey when superiors command a sin.
Letter to Hippolyte Courtès, 27 July 1831, EO VIII n 398