Matthew 15:11

Not that which goeth into the mouth defileth a man; but that which cometh out of the mouth, this defileth a man.

Ver. 11. Not that which goeth into the man, &c.] Whether with clean or foul hands, taken meat makes not the man guilty of God's wrath. What! not if abused to surfeiting and drunkenness? saith Bellarmine, who is angry with Christ for this doctrine (as making against theirs directly), and therefore seeks to disprove him. We answer for and with Christ: that he speaks here of the moderate use of meats, which is indifferent. As for the abuse of it to surfeiting and excess, this is an evil that cometh out of the heart, and defileth the man, as being a flat breach of the law of God, who everywhere condemns it.

But that which cometh out of the mouth] That is, out of the heart, that muck hill, through the mouth, as through a dung port, that defileth a man worse than any outhouse can do. Hence sin is called filthiness, abomination, the vomit of a dog, the devil's excrements, &c. The very visible heavens are defiled by it, and must therefore be purged by fire, as those vessels were that held the sin offering. As for the soul, sin sets such ingrained stains upon it, as nothing can fetch out but the blood of Christ, that spotless Lamb.