1 Timothy 4:2

"Consciences seared" refers to their final numbing, the deadening of their consciences.

In what way then is she a virgin who has fallen away from the faith, who has devoted herself to the deceivers, who obeys the demons and honors falsehood? In what way is she a virgin who has a seared conscience? For the virgin must be pure not only in body but also in soul if she is going to receive the holy bridegroom.… Virginity is defined by holiness of body and soul. But if a woman is unholy and impure in each respect, how could she be a virgin?… But she shows me a pale face, wasted limbs, a shabby garment and gentle glance.… What is the good of all that when the eye of the soul is bold, for what could be more audacious than that eye encouraging her real eyes to consider the objects of God's creation as bad?

"Speaking lies in hypocrisy." This implies that they utter not these falsehoods through ignorance and unknowingly, but as acting a part, knowing the truth, but "having their conscience seared," that is, being men of evil lives. But why does he speak only of these heretics? Christ had before said, "Offenses must need come" (Matt. xviii. 7), and he had predicted the same in his parable of the sower, and of the springing up of the tares. But here admire with me the prophetic gift of Paul, who, before the times in which they were to appear, specifies the time itself. As if he had said, Do not wonder, if, at the commencement of the faith, some endeavor to bring in these pernicious doctrines; since, after it has been established for a length of time, many shall depart from the faith.

That is, what they speak falsely about, they do not speak falsely out of ignorance, but knowing that it is false, they hypocritically teach it as though it were true.

On the part of those deceived, the cause is also twofold: one is their falsity; the other is the perversity of their conscience. In regard to the first he says, of devils, i.e., of men possessed by a Devil; of devils I say, speaking lies: …

(6.) Men must be hardened, and their consciences seared, before they can depart from the faith, and draw in others to side with them. (7.) It is a sign that men have departed from the faith when they will command what God has forbidden, such as saint and angel or demon-worship; and forbid what God has allowed or commanded, such as marriage and meats.

These will depart from the faith, by the hypocrisy of them that speak lies, having their own consciences as senseless and unfeeling as flesh that is seared with an hot iron.

Speaking lies in hypocrisy,....

Professing to lead others to holiness, their own conscience is all the while defiled. Bad consciences always have recourse to hypocrisy. As faith and a good conscience are joined (1Ti 1:5); so hypocrisy (that is, unbelief, Mt 24:5, 51; compare Lu 12:46) and a bad conscience here.

Speaking lies in hypocrisy - Persons pretending, not only to Divine inspiration, but also to extraordinary degrees of holiness, self-denial, mortification, etc., in order to accredit the lies and false doctrines which they taught. Multitudes of lies were framed concerning miracles wrought by the relics of departed saints, as they were termed. For, even in this country, Thomas a Becket was, deemed a saint, his relics wrought numerous miracles; and his tomb was frequented by multitudes of pilgrims! However, as he works none now, we may rest assured that he never did work any.

Speaking lies in hypocrisy - ἐν ὑποκρισει ψευδολόγων en hupokrisei pseudologōn. Or rather, “by, or through the hypocrisy of those speaking lies. So it is rendered by Whitby, Benson, Macknight, and others. Our translators have rendered it as if the word translated “speaking lies” - ψευδολόγων pseudologōn - referred to “demons,” or, “devils,” δαιμονίων daimoniōn - in the previous verse. But there are two objections to this. One is, that then, as Koppe observes, the words would have been inverted - ψευδολόγων ἐν ὑποκρίσει pseudologōn en hupokrisei. The other is, that if that construction is adopted, it must be carried through the sentence, and then all the phrases “speaking lies,” “having their conscience seared,” “forbidding to marry,” etc., must be referred to demons. The preposition ἐν en, “in” may denote “by” or “through,” and is often so used. If this be the true construction, then it will mean that those who departed from the faith did it “by” or “through” the hypocritical teachings of those who spoke lies, or who knew that they were inculcating falsehoods; of those whose conscience was seared; of those who forbade to marry, etc. The meaning then will be, “In the last days certain persons will depart from the faith of the gospel. This apostasy will essentially consist in their giving heed to spirits that lead to error, and in embracing corrupt and erroneous views on demonology, or in reference to invisible beings between us and God. This they will do through the hypocritical teaching of those who inculcate falsehood; whose consciences are seared,” etc. […]

I heard the Diabolist say, "I tell you I have done everything else. If I do that I shan't know the difference between right and wrong." I rushed out without daring to pause; and as I passed the fire I did not know whether it …