Thus when he heard anyone condemned as bad because he had committed a bad act, he took pains with his accustomed gentleness to modify the charge by making a distinction between _vice_ and _sin_, the former being a habit, the latter an isolated act. "Vice," he said, "is a habit, sin, the outcome of that habit; and just as one swallow does not make a summer, so one act of sin does not make a person vicious. That is to say, it does not render him a sinner in the sense of being steeped in and wholly given over to the dominion of the particular vice, the act of which he has committed once, or even more than once." Being asked whether in conformity with this principle it would not be equally wrong to praise anyone for a single act of virtue, as if that virtue were his or her constant habit, he replied: "You must remember that we are forbidden to judge our neighbour in the matter of the evil which he may appear to do, but not in the good. On the contrary, we may and should suppose that he has the good habit from which the act seen by us naturally springs. Nor can we err in such a supposition, since the very perfection of charity consists in its excess. But when we judge evil of others, our tongue is like the lancet in the surgeon's hand, and you know how careful he must be not to pierce an artery in opening a vein. We must only judge from what we see. We may say that a man has blasphemed and sworn, if we have heard him do so; but we may not in that account alone say that he is a blasphemer; that is, that he has contracted the habit of blasphemy, substituting the vice for the sin." The objection was raised that it would follow that we must never attempt to judge whether a person is or is not in a state of grace, however holy his life may seem to be; since no one knows whether he is worthy of love or of hate, and least of all we, who know our neighbour far less intimately than he knows himself. To this he replied, that if faith, according to St. James, is known by its works,[1] much more is charity so known, since it is a more active virtue, its works being the sparks from seeing which we learn that its fire is still burning somewhere. And though when we saw a sin, which is undoubtedly mortal, being committed, we might have said that the sinner was no longer in a state of grace, how do we know that a moment afterwards God may not have touched his heart, and that he may not have been converted from his evil ways by an act of contrition? This is why we must always fear to judge evil of others, but as regards judging well, we are free to do so as much as we please. Charity grows more and more by hoping all good of its neighbour, by thinking no evil, by rejoicing in truth and goodness, but not in iniquity. [Footnote 1: St. James ii. 17, 26.] UPON RIDICULING ONE'S NEIGHBOUR.