Conscience along with intuition are the senses of the human spirit. When the conscience is shut down, it is because it has become passive. Here is what Jessie Penn-Lewis in “War on the Saints” has written about this subject:
When believers sink into passivity of conscience, there is a manifestation of moral degradation in some, and in others stagnation, or retrogression in life or service. Instead of using their mind, or conscience in deciding what is good and evil, and right and wrong, they walk, as they believe, according to the “voice of God,” which they make the deciding factor in all their decisions. When this takes place, they will not listen to their reason, or conscience, or the words of others, and having come to decision through the supposed direction of God, their minds become as a closed and sealed book on the matter in question.
Ceasing to use their true reasoning powers, they become open to all kinds of suggestions from evil spirits, and false “reasonings”; for example, in regard to the coming of Christ, some have falsely reasoned that because Christ is coming soon, they do not need to carry on their usual work, overlooking the words of the Lord on this very matter: “Who then is the faithful and wise servant, whom his lord hath set over his household, to give them their food in due season? Blessed is that servant, whom his lord, when he cometh, shall find so doing.”
Because of what he will gain through it, therefore, the devil will do anything to engender passivity in any form whatsoever, in spirit, or mind or body.
Here is a recent example. A woman just wrote me and quoted the apostles asking some new converts this question: Have you received the Holy Ghost since you believed?” She passively accepted what she was taught, ie that tongues is the evidence that a person is saved. How does asking somebody a question CONFIRM or act as evidence of ANYTHING???? DA???? Look at that question closely. If they believed, were they not already saved? When I was saved, I too knew nothing about the Holy Ghost. Passivity of conscience has caused many to believe false doctrine of all kinds.