18. Knowing their malice. They had opened the conversation in such a manner that they did not appear to differ at all from excellent scholars. Whence then had Christ this knowledge, but because his Spirit was a discerner of hearts? It was not by human conjecture that he perceived their cunning, but because he was God he penetrated into their hearts, and therefore they gained nothing by attempting the concealment of flattery and of pretended righteousness Accordingly, before giving a reply, he exhibited a proof of his Divinity by laying open their concealed malice. Now since wicked men every day employ snares of the same kind, while their inward malice is concealed from us, we ought to pray to Christ to bestow upon us the spirit of discernment, and that what he had by nature and by his own right he may grant to us by a free gift. How much we need this prudence, is evident from the consideration that, if we do not guard against the snares of the wicked, we shall constantly expose the doctrine of God to their calumnies.