We do not want to believe anything less than that which is in the Bible. Neither do we want to believe any more than is in the Bible. The Devil tries to push us to either end. Here he attempts to make us overshoot the runway through legalism. Legalism is pseudo spirituality.
Religious types believe that there is something spiritual in asceticism.
The more they deny themselves, the more the impress God. The more miserable they make themselves the better their place with God. This word sends us back to verse fourteen. Jesus wiped out the ordinances against us on the cross. Old Testament ritual, restrictions and regulations were abolished on the cross yet many Christians today hang onto them.