'Be Not Deceived' in the Bible

Take heed to yourselves, that your heart be not deceived, and ye turn aside, and serve other gods, and worship them;

And he said, Take heed that ye be not deceived: for many shall come in my name, saying, I am Christ; and the time draweth near: go ye not therefore after them.

Know ye not that the unrighteous shall not inherit the kingdom of God? Be not deceived: neither fornicators, nor idolaters, nor adulterers, nor effeminate, nor abusers of themselves with mankind,

Be not deceived: evil communications corrupt good manners.

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

Be not deceived, my beloved brethren.