Do not be deceived: God cannot be mocked. People reap what they sow. (NIV)

Do not be deceived and deluded and misled; God will not allow Himself to be sneered at (scorned, disdained, or mocked by mere pretensions or professions, or by His precepts being set aside.) [He inevitably deludes himself who attempts to delude God.] For whatever a man sows, that and that only is what he will reap. (AMP)

Be not deceived; God is not mocked: for whatsoever a man soweth, that shall he also reap. (KJV)