Reply Obj. 1: The outward deed is a natural sign of the intention. Accordingly when a man does good works pertaining by their genus to the service of God, and seeks by their means to please, not God but man, he simulates a right intention which he has not. Wherefore Gregory says (Moral.) that "hypocrites make God's interests subservient to worldly purposes, since by making a show of saintly conduct they seek, not to turn men to God, but to draw to themselves the applause of their approval:" and so they make a lying pretense of having a good intention, which they have not, although they do not pretend to do a good deed without doing it.
Reply Obj. 2: The habit of holiness, for instance the religious or the clerical habit, signifies a state whereby one is bound to perform works of perfection. And so when a man puts on the habit of holiness, with the intention of entering the state of perfection, if he fail through weakness, he is not a dissembler or a hypocrite, because he is not bound to disclose his sin by laying aside the habit of holiness. If, however, he were to put on the habit of holiness in order to make a show of righteousness, he would be a hypocrite and a dissembler.
Reply Obj. 3: In dissimulation, as in a lie, there are two things: one by way of sign, the other by way of thing signified. Accordingly the evil intention in hypocrisy is considered as a thing signified, which does not tally with the sign: and the outward words, or deeds, or any sensible objects are considered in every dissimulation and lie as a sign. _______________________
THIRD ARTICLE [II-II, Q. 111, Art. 3]
Whether Hypocrisy Is Contrary to the Virtue of Truth?
Objection 1: It seems that hypocrisy is not contrary to the virtue of truth. For in dissimulation or hypocrisy there is a sign and a thing signified. Now with regard to neither of these does it seem to be opposed to any special virtue: for a hypocrite simulates any virtue, and by means of any virtuous deeds, such as fasting, prayer and alms deeds, as stated in Matt. 6:1-18. Therefore hypocrisy is not specially opposed to the virtue of truth.
Obj. 2: Further, all dissimulation seems to proceed from guile, wherefore it is opposed to simplicity. Now guile is opposed to prudence as above stated (Q. 55, A. 4). Therefore, hypocrisy which is dissimulation is not opposed to truth, but rather to prudence or simplicity.
Obj. 3: Further, the species of moral acts is taken from their end. Now the end of hypocrisy is the acquisition of gain or vainglory: wherefore a gloss on Job 27:8, "What is the hope of the hypocrite, if through covetousness he take by violence," says: "A hypocrite or, as the Latin has it, a dissimulator, is a covetous thief: for through desire of being honored for holiness, though guilty of wickedness, he steals praise for a life which is not his." [*The quotation is from St. Gregory's Moralia, Bk XVIII.] Therefore since covetousness or vainglory is not directly opposed to truth, it seems that neither is hypocrisy or dissimulation.
On the contrary, All dissimulation is a lie, as stated above (A. 1). Now a lie is directly opposed to truth. Therefore dissimulation or hypocrisy is also.
I answer that, According to the Philosopher (Metaph. text. 13, 24, x), "contrariety is opposition as regards form," i.e. the specific form. Accordingly we must reply that dissimulation or hypocrisy may be opposed to a virtue in two ways, in one way directly, in another way indirectly. Its direct opposition or contrariety is to be considered with regard to the very species of the act, and this species depends on that act's proper object. Wherefore since hypocrisy is a kind of dissimulation, whereby a man simulates a character which is not his, as stated in the preceding article, it follows that it is directly opposed to truth whereby a man shows himself in life and speech to be what he is, as stated in Ethic. iv, 7.