2. Opinions of Others

26. About the last two, namely the useful and jocose lie [nn.24-25], it is commonly admitted that neither of them is a mortal sin in the case of imperfect men, because neither is per se against charity, nor even against anything that is of itself necessarily required for the state of those persons.

27. But in the case of perfect men both lies are said by some to be mortal sins, because the authority of these men is taken away so that they are not believed, and in this they make their state to be cheapened and even harm their hearers because of the scandal.

28. An argument against this [n.27] is that no circumstance makes what in one person is a venial sin to be in another a mortal sin unless one of the persons is necessarily obligated to what the other is not obligated to. But a perfect man does not obligate himself to keeping truth in his words, either by a vow or an oath, more than any other Christian does. Therefore the circumstance of the person (because the person is not specially obligated) does not change a venial sin into a mortal sin.