“a dreamer of dreams,” along with the prophet, answers the two media of divine revelation, the vision and the dream, by which, according to Num 12:6, God made known His will. With regard to the signs and wonders (mopheth, see at Exo 4:21) with which such a prophet might seek to accredit his higher mission, it is taken for granted that they come to pass (בּוא); yet for all that, the Israelites were to give no heed to such a prophet, to walk after other gods. It follows from this, that the person had not been sent by God, but as a false prophet, and that the signs and wonders which he gave were not wonders effected by God, but σημεῖα καὶ τέρατα ψεύδους (“lying sings and wonders,” 2Th 2:9); i.e., not merely seeming miracles, but miracles wrought in the power of the wicked one, Satan, the possibility and reality of which even Christ attests (Mat 24:24). - The word לאמר, saying, is dependent upon the principal verb of the sentence: “if a prophet rise up...saying, We will go after other gods.”
Verse 4
God permitted false prophets to rise up with such wonders, to try the Israelites, whether they loved Him, the Lord their God, with all their heart. (נסּה as in Gen 22:1.) אהבים הישׁכם, whether ye are loving, i.e., faithfully maintain your love to the Lord. It is evident from this, “that however great the importance attached to signs and wonders, they were not to be regarded among the Israelites, either as the highest test, or as absolutely decisive, but that there was a certainty in Israel, which was so much the more certain and firm than any proof from miracles could be, that it might be most decidedly opposed to it” (Baumgarten). This certainty, however, was not “the knowledge of Jehovah,” as B. supposes; but as Luther correctly observes, “the word of God, which had already been received, and confirmed by its own signs,” and which the Israelites were to preserve and hold fast, without adding or subtracting anything. “In opposition to such a word, no prophets were to be received, although they rained signs and wonders; not even an angel from heaven, as Paul says in Gal 1:8.” The command to hearken to the prophets whom the Lord would send at a future time (Deu 18:18.), is not at variance with this: for even their announcements were to be judged according to the standard of the fixed word of God that had been already given; and so far as they proclaimed anything new, the fact that what they announced did not occur was to be the criterion that they had not spoken in the name of the Lord, but in that of other gods (Deu 18:21-22), so that even there the signs and wonders of the prophets are not made the criteria of their divine
