Musar su Salmi 81:10

[And in this manner I have explained the verse in Psalms 81:10: "There shall not be in you a strange god and you shall not bow down to a foreign god. (11) I am the L-rd your G-d who brought you up from the land of Egypt. Open wide your mouth and I will fill it." Now, ostensibly, it should first have been written "I am the L-rd your G-d, etc." and only then "There shall not be in you a strange god," as it is written in the Torah. Why is the order reversed? But, Chazal have told us (Shabbath 105b): "Which is the strange god in the body of a man? The yetzer hara." (In the beginning it incites him to commit transgressions which are not so severe; but, in the end, "transgression breeds transgression," and it permits him even to bow down to idols.) And the intent of the verse [in Psalms]: "I am the L-rd your G-d, etc." is: Have I not brought you up from the land of Egypt so that you receive the Torah, as it is written (Shemoth 3:12): "And this is the sign for you [Moses] that I have sent you. When you take out the people from Egypt, you will serve G-d on this mountain." For this [the receiving of the Torah] is the purpose of the exodus, as Rashi explains. Therefore, "open wide your mouth and I will fill it." This is like a rabbi's telling his disciple: "Open up your mouth and let your words shine forth." For the Holy One Blessed be He wishes to give each Jew a great share in the Torah. However, in truth, everything is dependent upon the power of the recipient, wherefore He says: "Open wide your mouth." That is, ready yourself to receive much, and I will fill it according to your widening. But this is prefaced by: When will this be fulfilled in you? When "there will not be in you a strange god," when the yetzer hara will not be a guest in your body. Then you will be able to open wide your mouth to Torah, and I will fill it. For it is to this end that I brought you up from the land of Egypt (As it is written (Ibid. 13:9): "And it shall be a sign upon your hand… so that the Torah of the L-rd shall be in your mouth.") But if there is a strange god in your body— that is, if it is full of lewd thoughts, G-d forbid, I will not be able to fulfill your wish to widen your mouth with Torah.

In addition to this common factor which links every Israelite with one another to form part of the whole, each Israelite is a distinct individual as is evident from a statement by our sages (Bamidbar Rabbah 21,22, based on Isaiah 4,5): "any righteous person is burned or singed by the fire G–d has provided as part of the canopy He grants to every righteous person." This teaches that though every Israelite has his share in the World to Come, everyone is assigned a place of his own. Concerning this state of affairs, Moses said in 32,12: "The Lord guided him separately, unaccompanied by any alien power." The word ינחנו in this verse is a singular, (guided him, not guided us) to stress that every Israelite is an individual unit, personality. When Moses continued that: "He was not accompanied by another power," this refers to the שרים and מזלות assigned to guide the fates of the Gentiles. None of those forces exercise the slightest control over the Jewish people. The two commandments in these last three portions directly reflect these thoughts. The commandment of Hakhel, demanding that all of Israel – women and childen included – assemble in the courtyard of the Holy Temple to listen to a reading of the Torah, is rooted in the fact that all of Israel is perceived of as a single body. Subsequently the Torah once more instructs every individual Israelite separately to write a copy of the Torah for himself. As long as Israel perform G–d's commandments they experience a close affinity with G–d both on a national and on an individual level. If, G–d forbid, they were to fail to observe the Torah's commandments, they would find themselves under the influence of אל נכר, an alien deity, i.e. Satan, the evil urge (mentioned in ראשית חכמה, שער ענוה נ"ז). When this happens, the sinner will find himself in the domain of "the left side of the emanations," i.e. subject to influences similar to those which govern the lives of the Gentiles.

And you must be very careful not to do damage in your anger, for our Rabbis said : "He who rends his garments, breaks his utensils in his wrath and scatters his money should be in your eyes like one who worships idols" (Shabbath 105b). For this is the artful craft of the Evil Desire. Today he says to a man, "Do thus." And on the morrow he says to him, "Go ahead and serve idols." And the man goes and serves. This is the reason it is written "There shall not be in you a strange god" (Ps. 81:10). Now which strange god can be inside of a man? You must necessarily say, "It is the Evil Desire." Look and see how the Evil Desire strenthens itself in a man in a time of anger.