THE GOSPEL ACCORDING TO MATTHEW - Chapter 15 - Verse 9
Verse 9. In vain they do worship me. That is, their attempts to worship are vain, or are not real worship—they are mere forms.
Teaching for doctrines, etc. The word doctrines, here, means the requirements of religion—things to be believed and practised in religion. God only has a right to declare what shall be done in his service; but they held their traditions to be superior to the written word of God, and taught them as doctrines binding the conscience.
See Barnes on "Mt 15:1"
{g} "for doctrines" Col 2:22