The way to a reprobate mind begins by - 

"The shrinking from difficulty, the dread of ridicule, the love of ease, which drains off the sap of a man's moral earnestness, soon dry up the sources of all moral faith from the very roots of him. Though in one sense it is true that he must believe before he acts, yet assuredly he will not long go on believing, when he has ceased to act. 

They plainly show, that any truth a man ceases to live by necessarily becomes to him, if he only persevere, an entire falsehood. God insists on having a concurrence between our practice and our thought. If we proceed to make a contradiction between them, he forthwith begins to abolish it: and if the Will does not rise to the Reason, the Reason must be degraded to the Will. This is no other than that "giving over of men to a reprobate mind," by which "the truth of God is changed into a lie." James Martineau.