Tafsiran Bilangan 15:41: Rashi, Sforno, Rabbeinu Bahya & Siftei Chakhamim

אני ה׳ I AM THE LORD Who am faithful to give reward.

'אני ה' אלוקיכם אשר הוצאתי אתכם וגו...אני ה, the reason why I orchestrated your redemption from slavery in Egypt was so that I would be your exclusive G’d, that your existence and well being on earth should be based on a reciprocal relationship not requiring an intermediary. The parameters of this existence should be enduring, not subject to change throughout history. You will be like other parts of the universe which endure eternally

אני ה' אלו-היכם אשר הוצאתי אתכם מארץ מצרים להיות לכם לאלו-הים, אני ה' אלו-היכם, “I am the Lord your G’d who has taken you out of the land of Egypt in order to become your G’d, I am the Lord your G’d.” Here the Torah reveals that the purpose of the Exodus was in order for Hashem to become our G’d. If that is so, we can look at the Exodus as something which did not only benefit the Jewish people but as something which bestowed similar benefits on G’d Himself. This is what Joshua had in mind when he said (Joshua 7,9) “if they will destroy our name from earth what are You going to do for Your great name?” If G’d does not have a people how could the fact of His kingdom become manifest on earth?
Our verse commenced with the words: “I am the Lord your G’d,” and it concludes with the very same words. The reason this has been repeated is to remind us that G’d’s status vis-a-vis us in the hereafter will remain the same as it is in our terrestrial world.

אלהיכם YOUR GOD Who am certain to exact punishment (cf. Sifrei Bamidbar 115:1).