Matthew 15:13 - Ellicott's Commentary On The Whole Bible

Every plant, which my heavenly Father hath not planted. — The disciples could hardly fail to connect the words with the parable which they had heard so lately. The system and the men that they had been taught to regard as pre-eminently religious were, after all, in their Master’s judgment, as the tares and not as the wheat (Matthew 13:37-38). So far as they were a sect or party, His Father had not planted them. They, too, were left, according to the teaching of that parable, to grow until the harvest, but their end was sure — they should be “rooted out.” The words which proclaim their doom were, however, intentionally general in their form. In that divine judgment which works through the world’s history, foreshadowing the issues of the last great day, that doom is written on every system, party, sect which originates in man’s zeal, in narrowness, in self-will. It has not been planted by the Father, and therefore it is doomed to perish.