Conscience is the aboriginal Vicar of Christ...

"Conscience is not a long-sighted selfishness, nor a desire to be consistent with oneself; but it is a messenger from Him, Who, both in nature and grace, speaks to us behind a veil, and teaches and rules us by His representatives. Conscience is the aboriginal Vicar of Christ." In pp.250 also:"Conscience has its rights because it has duties; but in this age, with a large portion of the public, it is the very right and freedom of conscience, to ignore a Lawgiver and Judge, to be independent of unseen obligations. It has become a license to take up any or no religion, to take up this or that and let it go again, to go to church, to go to chapel, to boast of being above all religions and to be an impartial critic of each of them. Conscience is a stern monitor, but in this century it has been superseded by a counterfeit, which the eighteen centuries prior to it never heard of, and could not have mistaken for it, if they had. It is the right of self will.”

...by John Henry Newman, in his “Letter to the Duke of Norfolk” (December 27, 1874, pp.248-250. *If you want to explore more: http://www.newmanreader.org