But he answered and said, Every plant, which my heavenly Father hath not planted, shall be rooted up.

People's New Testament

15:13 Every plant. A general truth, but here refers to the doctrines not of God, like the tradition of the elders (Mt 15:2).

Wesley's Notes

15:13 Every plant - That is, every doctrine.

Jamieson-Fausset-Brown Bible Commentary

13. But he answered and said, Every plant, which my heavenly Father hath not planted, shall be rooted up-They are offended, are they? Heed it not: their corrupt teaching is already doomed: the garden of the Lord upon earth, too long cumbered with their presence, shall yet be purged of them and their accursed system: yea, and whatsoever is not of the planting of My heavenly Father, the great Husbandman (Joh 15:1), shall share the same fate.

Matthew Henry's Concise Commentary

15:10-20 Christ shows that the defilement they ought to fear, was not from what entered their mouths as food, but from what came out of their mouths, which showed the wickedness of their hearts. Nothing will last in the soul but the regenerating graces of the Holy Spirit; and nothing should be admitted into the church but what is from above; therefore, whoever is offended by a plain, seasonable declaration of the truth, we should not be troubled at it. The disciples ask to be better taught as to this matter. Where a weak head doubts concerning any word of Christ, an upright heart and a willing mind seek for instruction. It is the heart that is desperately wicked, Jer 17:9, for there is no sin in word or deed, which was not first in the heart. They all come out of the man, and are fruits of that wickedness which is in the heart, and is wrought there. When Christ teaches, he will show men the deceitfulness and wickedness of their own hearts; he will teach them to humble themselves, and to seek to be cleansed in the Fountain opened for sin and uncleanness.