(_a_) _Excusable ignorance._ As has been pointed out, a man is only guilty of mortal sin, when he is ignorant that the act is forbidden. S. Paul says, "As many as have sinned without law, shall also perish without law; and as many as have sinned in the law, shall be judged by the law." And our Lord Himself, "That servant which knew his Lord's will, and prepared not himself, neither did according to his will, shall be beaten with many stripes; but he that knew not, and did commit things worthy of stripes, shall be beaten with few stripes. For unto whomsoever much is given, of him shall be much required; and to whom men have committed much, of him they will ask the more." (Luke xiii. 47, 48.) But the ignorance must be excusable, that is to say, he who is in ignorance must not be in _wilful_ ignorance. (_b_) _Fear._ In certain circumstances the mind may be in such a state of alarm and disturbance that its power of judgment is paralyzed, and the will is overborne by the fear which has become dominant. It is said of those who are out of their minds that they are not accountable for their actions, and there are cases in which terror is so acute, and so overmastering, that a man or woman ceases to be morally responsible for what he or she does. (_c_) _Compulsion._ As already shewn, liberty is essential to qualify an act as either culpable or not culpable to the person who is the agent. An act may be in itself wrong, but the guilt entailed on the soul of him who does it depends on whether he be a free agent or not. For instance, it often happened that a martyr was forced to offer incense to idols. The grains were thrust into his hand, and the hand was extended by violence over the fire of the altar. But as the soul of the martyr never yielded consent, no guilt of apostasy attached to it. (_d_) _Inadvertence_, or excusable want of attention. It does often happen that a wrong act is done before we really know what we are about. It is done without premeditation. We are of course bound to be ever on our guard against temptation; but that sin into which we have fallen _unintentionally_ does not carry with it the same guilt to the soul as if it had been done with deliberation. "Be not high-minded, but fear," says the Apostle. The Evil One is ever on the watch to entrap us when unprepared into sin. And though a sin committed inadvertently may not be mortally sinful, yet it may, and probably will, carry with it the temporal consequences just the same as if it had been committed deliberately. "Watch and pray lest ye enter into temptation." S. Peter denied his Master partly through fear, partly through inadvertence, he was caught off his guard. We stand often without any sight of or suspicion of the temptation on the brink of which we are, and with a touch we are over. As we are repeatedly warned to caution and watchfulness, such inadvertence does not wholly excuse us. We are _bound_ to be ever prepared, nevertheless the nature of man is weak and frail.