If there arise among you a prophet, or a dreamer of dreams, and gives you a sign or a wonder, and the sign or the wonder come to pass, whereof he spoke to you, saying, “Let us go after other gods, which you have not known, and let us serve them;”
You shall not listen to the words of that prophet, or that dreamer of dreams: for the LORD your God proves you, to know whether you love the LORD your God with all your heart and with all your soul.
Deut 13:1-3
And no marvel; for Satan himself is transformed into an angel of light.
2Cor 11:14
But though we, or an angel from heaven, should preach unto you any gospel other than that which we preached unto you, let him be anathema.
Gal 1:8