The fifth reason is that frequently, not only can words be heard, but, in a way which I shall never be able to explain, much more can be understood than the words themselves convey and this without any further utterance. Of this way of understanding I shall say more elsewhere; it is a very subtle thing, for which Our Lord should be praised. Some people (especially one person with experience of these things, and no doubt others also) have been very dubious about this way of understanding locutions and about the differences between them, and have been quite unable to get the matter straight. I know that this person has thought it all over very carefully, because the Lord has granted her this favour very frequently indeed; her most serious doubt, which used to occur when she first experienced it, was whether she was not imagining the whole thing. When locutions come from the devil their source can be more quickly recognized, though his wiles are so numerous that he can readily counterfeit the spirit of light. He will do this, in my view, by pronouncing his words very clearly, so that there will be no more doubt about their being understood than if they were being spoken by the spirit of truth. But he will not be able to counterfeit the effects which have been described, or to leave in the soul this peace or light, but only restlessness and turmoil. He can do little or no harm if the soul is humble and does what I have said -- that is, if it refrains from action, whatever the locutions may say.