Luke 6:49

(Hom. 24. in Matt.) The Lord also shows us that faith profiteth a man nothing, if his manner of life be corrupt. Hence it follows, But he that heareth and doeth not, is like a man, that without a foundation, built an house upon the earth, &c.

Or they build upon the earth without foundation, who upon the quicksand of doubt, which relates to opinion, lay the foundation of their spiritual building, which a few drops of temptation wash away.

The house of the devil is the world which lieth in wickedness, (1 John 5:19.) which he builds upon the earth, because those who obey him he drags down from heaven to earth; he builds without foundation, for sin has no foundation, standing not by its own nature, for evil is without substance, which yet whatever it is, grows up in the nature of good. But because the foundation is called so from fundus, we may not unfitly understand that fundamentum is placed here for fundus. As then he who is fallen into a well is kept at the bottom of the well, so the soul falling away remains stationary, as it were, at the very bottom, as long as it continues in any measure of sin. But not content with the sin into which it is fallen, while daily sinking into worse, it can find no bottom, as it were, in the well to which it may fix itself. But every kind of temptation increasing, both the really bad and the feignedly good become worse, until at last they come to everlasting punishment. Hence it follows, Against which the stream did beat vehemently. By the force of the stream may be understood the trial of the last judgment, when both houses being finished, the wicked shall go into everlasting punishment, but the righteous into life eternal. (Mat. 25:46.)

Or, He teaches that the obedience to heavenly precepts is the foundation of all virtue, by means of which this our house can be moved neither by the torrent of pleasures, nor by the violence of spiritual wickedness, neither by the storms of this world, nor by the cloudy disputations of heretics; hence it follows, But the flood came, &c.