Midrash su Deuteronomio 23:21

“Since the king's word has power, and who will say to him: What are you doing” (Ecclesiastes 8:4).
“Since the king's word has power.” Rabbi Bon said: It is written: “Do not test [the Lord]” (Deuteronomy 6:16), “and God tested [Abraham]” (Genesis 22:1), “Do not take vengeance and do not bear a grudge” (Leviticus 19:18), “the Lord is a zealous and vengeful God” (Nahum 1:2). [This is analogous] to a rabbi who would command his disciple, and say to him: ‘Do not divert judgment,’ but he [the rabbi] diverts judgment; ‘do not give preferential treatment,’ but he gives preferential treatment.²²A parallel midrash (Bereshit Rabba 55:3) adds the example: The rabbi tells him not to lend with interest, but he lends with interest. The disciple said to him: ‘Rabbi, for you it is permitted and for me it is prohibited?’ [The rabbi] said to him: ‘I am telling you only that you may not lend to an Israelite with interest, but lend to a gentile, as it is written: “You may take interest from a gentile” (Deuteronomy 23:21).’²³Thus, the rabbi informs his disciple that he did not fully understand any of the rabbi’s actions. So too, Israel said before the Holy One blessed be He: ‘Master of the universe, did You not write in Your Torah: “Do not take vengeance and do not bear a grudge” (Leviticus 19:18)? But You take vengeance and bear a grudge.’ He said to them: ‘I will not bear a grudge against Israel, as it is written: “He will not contend to eternity or forever bear a grudge” (Psalms 103:9); however, for the nations of the world: “The Lord is vengeful to His foes and bears a grudge against His enemies” (Nahum 1:2). I dictated to you in My Torah: “Do not take vengeance and do not bear a grudge against the members of your people” (Leviticus 19:18), but you may take vengeance against the nations of the world, as it is stated: “Avenge the children of Israel [on the Midianites]” (Numbers 31:2),’ to realize what is written: “Since the king's word has power, [and who will say to him: What are you doing].”

(Exod. 22:24 [25]:) IF [YOU LEND] MONEY [TO MY PEOPLE], <TO THE POOR PERSON WITH YOU, YOU SHALL NOT ACT TOWARD HIM AS A CREDITOR >. You shall not say: <The verse concerns only> money. Rather <it includes> anything else which you might lend him.³²See BM 71a; Mekhilta de Rabbi Ishamael, Kaspa 1. YOU SHALL NOT ACT TOWARD HIM AS A CREDITOR. So do not say: In the case of money, Torah says not to loan at interest, <but> I am making a loan to him with wheat.³³If the value of wheat rises, then the lender gets his profit. Thus it is stated <in this extended sense > (in Exod. 22:24 [25]): IF YOU LEND MONEY TO MY PEOPLE, TO THE POOR PERSON WITH YOU. Therefore, one looks at a poor person as though he were WITH YOU. Hence our masters have said: In the case of a poor person who is in the market and a poor person [in your own courtyard], the one in the courtyard < being nearer > has precedence <in receiving a loan>. In the case of a poor person dwelling near you and one dwelling in another city, the poor person nearer you has precedence. (Exod. 22:24 [25]:) <IF YOU LEND MONEY…> TO THE POOR PERSON WITH YOU, to that poor person who is WITH YOU and one of your own, YOU SHALL NOT ACT TOWARD HIM AS A CREDITOR. <Do> not <think>, because of what I told you (in Deut. 23:21 [20]): FOR A FOREIGNER YOU MAY DEDUCT INTEREST, <that> you shall lend to a foreigner and abandon Israel by saying: I am profiting from the foreigner. The Holy One has said: Know that I am the one who has made him poor and you rich. I can make you poor again.³⁴See Lev. R. 34:4. Rav Nahman said: [See] what is written (in Deut. 15:10): GIVE TO HIM READILY […], <FOR BECAUSE OF THIS DEED THE LORD YOUR GOD WILL BLESS YOU>.³⁵Tanh., Exod. 6:15. "For the sake of (lema'an)" is not written here, <but> {IF} BECAUSE OF THIS DEED. What is the meaning of BECAUSE OF (GLL)? Know that it is "wheel" (rt.: GLL).³⁶On the interchange of riches and poverty as a rotating wheel, see Shab. 151b (bar.); Exod. R. 31:3, 14; Lev. R. 34:3; Ruth R. 5:9. I have made him poor and you rich. Do not cause me to turn back the wheel and make you poor. R. Shelah said: See what is written (in vs. 7): DO NOT HARDEN YOUR HEART <AND SHUT YOUR HAND> [AGAINST YOUR <POOR> RELATION]. What is the meaning of AGAINST YOUR … RELATION? "Against a <poor> person" is not written here, but AGAINST YOUR <POOR> RELATION, because the two of you are on a par. Do not cause me to turn back the wheel and make you like him.

Another opinion: “The Lord tests the righteous.” – This is Abraham – “Sometime after these things, God tested Abraham.” R. Avin expounded: (Ecclesiastes 8:4) “Since a king's word is supreme, who can say to him: ‘What are you doing?’” – R. Avin said: [This may be compared] to a teacher who commands his student, saying to him: (Deuteronomy 16:19) “You shall not judge unfairly,” but [the teacher himself] judges unfairly; (Deuteronomy 16:19) “Do not take a bribe,” but [the teacher himself] takes a bribe; Do not lend on interest, but [the teacher himself] lends on interest. His student said to him: Rabbi, you said to me: Do not lend on interest, but you lend on interest? [Is it] permitted to you but forbidden to me? [The teacher] said to him: I said to you: Do not lend on interest to a Jew, but you may lend on interest to an idol worshipper, as it is written: (Deuteronomy 23:21) “You may lend on interest to a foreigner, but you may not lend on interest to your brother [Israelite].” Thus Israel said before The Holy One Blessed be He: Master of the Universe, you wrote in your Torah: (Leviticus 19:18) “You shall not take vengeance or bear a grudge,” but you take vengeance and bear a grudge, as it is said: (Nahum 1:2) “The Lord is vengeful and fierce in wrath. The Lord takes vengeance on His enemies.” The Holy One Blessed be He said to them: I wrote in the Torah: (Leviticus 19:18) “You shall not take vengeance or bear a grudge against your countrymen,” but I take vengeance against idol worshippers – (Numbers 31:2) “Avenge the Israelite people on the Midianites.” It is written: (Deuteronomy 6:16) “Do not test the Lord” – [but] “God tested Abraham.”