Now this is at once to accuse, and to give demonstration of His own sayings from their case. For behold, says He, you being evil trees, cannot bring forth good fruit. I do not then marvel at your talking thus: for you were both ill nurtured, being of wicked ancestors, and you have acquired a bad mind.
And see how carefully, and without any hold for exception, He has expressed His accusations: in that He said not, How can you speak good things, being a generation of vipers? (for this latter is nothing to the former): but, How can you, being evil, speak good things?
But He called them broods of vipers, because they prided themselves on their forefathers. To signify therefore that they had no advantage thereby, He both casts them out from their relationship to Abraham, and assigns them forefathers of kindred disposition, having stripped them of that ground of illustriousness.
For out of the abundance of the heart the mouth speaks. Here again He indicates His Godhead, which knew t...