These people honor me with their lips, but their hearts are far from me. They worship me in vain; their teachings are but rules made by man.
The Teacher is judging a religion that looks and sounds right, but has no heart - no real concern - for what God wants.
Jesus accuses them of paying lip service to the command to honor their parents. By a clever legal maneuver – dedicating all their money to God - they evaded responsibility for aged parents.
Conveniently, under the terms of the gift, they could still freely spend money on themselves. They were only forbidden to aid anyone else.
Thus, in the name of religion, they set aside God’s command to honor parents. And all the while appearing very religious. You can almost hear them – All our money is going to God’s temple after we die!
Why do such things happen? Perhaps, because not everything God asks of us is easy. Some things require sacrifice, effort, or even pain.
No problem! Create a loop-hole! A little theological slight of hand and all the difficult things magically disappear.
Unfortunately, what’s left is only a pretense of pleasing God.
The Teacher says - That’s lip service.