Having a form of godliness but denying its power. Have nothing to do with such people. (NIV)
For [although] they hold a form of piety (true religion), they deny and reject and are strangers to the power of it [their conduct belies the genuineness of their profession]. Avoid [all] such people [turn away from them]. (AMP)
Having a form of godliness, but denying the power thereof: from such turn away. (KJV)