פירוש על דברים 9:4

אל תאמר בלבבך SAY NOT IN THY HEART, “My righteousness and the wickedness of these nations brought it about that I possess the land;

SPEAK NOT THOU IN THY HEART. After cautioning that you should not think ‘my power and the might of my hand hath gotten me this wealth.’¹¹⁹Above, 8:17. but instead you are to know that the power over the vanquished was given to you by G-d, and that [the victory over] their mighty ones and fortified cities that you will have conquered [was made possible by] G-d in His Glory Who did it for you in a generally known miracle from Him, he further warned them, “Do not think that G-d did all this for you because of your righteousness; rather, He has done so for you only because of the wickedness of these nations.”¹²⁰Verse 5. Now this is a cause for the destruction of these nations, but he gave no reason for Israel’s possession of the Land. Therefore he reverted and explained, Not for thy righteousness¹²⁰Verse 5. that you will be righteous in conduct, nor even because of the upright heart that you will have, but only because of the wickedness of these nations will they be destroyed, and because of [His] oath to your fathers will you possess the Land, for your sin cannot annul the gift He gave to your fathers since He gave it to them by an oath. And Rashi wrote: “Speak not thou in thy heart — my righteousness and the wickedness of these nations caused me [to possess the Land]. Not for thy righteousness.” But this is not correct.¹²¹Rashi explained that they were not to think that a combination of their righteousness and the wickedness of the nations was a cause of one thing — their coming into the possession of the Land. On this Ramban comments that the verses indicate instead that there are two separate warnings here: “Do not think that because of your righteousness you are coming to possess the Land, and do not think that because of the wickedness of these nations they are driven out from it” (Mizrachi).
Now one should ask, “Has he not said, But because the Eternal loved you,¹²²Above, 7:8. thus establishing that they are beloved on high, and, [as we know], G-d loves only those who are good, for the wicked and him that loveth violence His soul hateth,¹²³Psalms 11:5. and if so, [it is justifiable that] they come to possess the Land also for their [own] righteousness [so, how can he say here Not for thy righteousness, etc.]?” The answer is that there he speaks of Israel in general, and here he reproves that particular generation that has been rebellious against the Eternal from the day they were in the wilderness.

אל תאמר בלבבך בהדוף, when you see that you enjoy victory against all odds, so that you realise this victory has to be credited to your enjoying a heavenly assist, do not commit a terrible error.