Matthew 15:7

Ye hypocrites, well did Isaiah prophesy of you, saying, This people honoreth me with their lips; But their heart is far from me. But in vain do they worship me, Teaching as their doctrines the precepts of men. - Isaiah 29:13.

This prophecy from Isaiah 29:13 contains in its last four words the key to failure in religion, "the precepts of men." If worship of God is to be undertaken on any basis that assures acceptance and ultimate reward, it must be on the basis of revelation. The precepts of men are without any value at all in this whole area. "Is it from heaven or from men?" (Matthew 21:25). That is the most important and relevant question that can be confronted with regard to any doctrine or practice connected with religion. There are literally hundreds of things widely observed in Christian worship throughout Christendom which should be challenged and rejected in the light of this teaching.