Deuteronomy 13:1 WEB

¹  If there arise in the midst of you a prophet, or a dreamer of dreams, and he give you a sign or a wonder,

²  and the sign or the wonder come to pass, of which he spoke to you, saying, Let us go after other gods, which you have not known, and let us serve them;

³  you shall not listen to the words of that prophet, or to that dreamer of dreams: for Yahweh your God proves you, to know whether you love Yahweh your God with all your heart and with all your soul.