ייִדישער מחשבֿה אויף דברים 4:26

The more likely explanation, then, is as I have written, that because reason would arrive at the opposite of these two commandments, it was necessary that we hear them from the All-Powerful Himself. And even if one would contend that though reason concluded that the Blessed One does not command us or exhort us and that it is inappropriate to serve Him as we do, still it would not conclude that we should therefore serve idols — it would still be necessary for us to have heard "You shall not have any other gods" from the All-Powerful Himself. The explanation is as I have already written. The first commandment is to believe that the Blessed One concerns Himself with us and commands and exhorts us. Now there is no doubt that intellect would decree the opposite of this, regarding it as the ascription of imperfection to the Blessed One. Having to hear this command then from the All-Powerful Himself, not befitting us to believe it from anyone else, it was necessary that the L-rd speak thus with us: "I am that Necessary Cause from whom there come to you mitzvoth and exhortations, commanding you [in this instance] not to do this thing [to have other gods]. And, from this point on, now that you know for a certainty that I command and exhort you, it behooves you to believe the additional mitzvoth and exhortations by way of the prophets." The nature of the matter demands that we hear from Him at this juncture a command or exhortation, whether it be close to intellect or distant from it; and He chose the mitzvah to be the exhortation against idolatry, it being the most appropriate to issue from His own mouth, especially so in that service of the Blessed One Himself is so antagonistic to reason that all of the nations gravitated to idol worship, for which reason the Torah repeatedly exhorted against it. And we have been informed in this parshah that the Blessed One does not delay the punishment of the idolator, as it is written (Deuteronomy 4:26): "I call heaven and earth to witness against you this day that you shall soon perish…"