Midrash sa Isaias 41:8: Midrash Tanchuma, Midrash Tanchuma Buber, Bamidbar Rabbah & Esther Rabbah

You find that anyone who observes the commandments meticulously is rewarded fully. For example, because Abraham observed the commandments meticulously, he was called the beloved of the Holy One, blessed be He, as it is said: The seed of Abraham, My beloved (Isa. 41:8). R. Samuel the son of Nahmani quoted R. Jonathan as saying that in Abraham’s home, even the commandment prohibiting the preparation of the Sabbath meals on a holy day that occurred on a Friday was carefully observed,²A dish prepared on Thursday is allowed to lay over until eaten on the Sabbath. By this legal fiction all the cooking for the Sabbath performed on a Friday that is a holy day is considered a continuation of the preparations started on Thursday. as it is said: Because that Abraham hearkened to My voice, and kept My charge, My commandments, My statutes, and My laws (Gen. 26:5). Are there a variety of laws that Scripture should say My laws? Has it not already been stated: One law shall be to him that is home born, and to the stranger that sojourns among you (Exod. 12:49), and was it not previously written: One law and one ordinance (Num. 15:16)? The word My laws employed in the above verse refers (solely) to the minutiae of the law which Abraham observed meticulously. The Holy One, blessed be He, said to him: Though you do observe My laws scrupulously, yet you dwell amongst idolaters; Get thee out of thy country.

(Numb. 13:2:) “Send men.” R. Aha the Great opened [his discourse] (with Is. 40:8), “Grass withers, flowers fade, but the word of our God shall stand forever.”⁷Numb. R. 16:3. To what is the matter comparable? To a king who had a friend. Now he made an agreement with him and said to him, “Come with me, and I will give you a present.” He went with him but died. The king said to the son of his friend, “Although your father has died, I am not withdrawing the present that I had promised to give him. Come and get it.” This king is the Holy One, blessed be He, and the friend is Abraham, as stated (in Is. 41:8), “the seed of My friend Abraham.” The Holy One, blessed be He, said to him, “Come with me,” as stated (in Gen. 12:1), “Go from your land….” He made an agreement with him to give him the Land of Canaan as a present, as stated (in Gen. 13:17), “Arise, walk about the land [… for I am giving it to you].” It also says (in vs. 15), “For all the land which you see, [to you will I give it, and to your seed forever].” The Holy One, blessed be He, said to Moses, “Although the ancestors have died, I had agreed with them to give them the land. I am not going back on [My word].” Instead (as in Numb. 13:2), “Send men.” Ergo (according to Is. 40:8), “but the word of our God shall stand forever.”

(Numb. 13:2:) SEND MEN…. R. Aha the Great opened (with Is. 40:8): GRASS WITHERS, FLOWERS FADE, BUT THE WORD OF OUR GOD SHALL STAND FOREVER.⁷Tanh., Numb. 4:3; Numb. R. 16:3. To what is the matter comparable? To a king who had a friend. Now he made an agreement with him and said to him: Come with me, and I will give you a present. He went with him but died. The king said to the son of his friend: Although your father has died, I am not withdrawing the present that I had promised to give him. Come and get it. This king is the Holy One, and the friend is Abraham, as stated (in Is. 41:8): THE SEED OF MY FRIEND ABRAHAM. The Holy One said to him: Come with me, as stated (in Gen. 12:1): GO FROM YOUR LAND. He made an agreement with him to give him a present, as stated (in Gen. 13:17): ARISE, WALK ABOUT THE LAND […], FOR I AM GIVING IT TO YOU. It also says (in vs. 15): FOR ALL THE LAND WHICH YOU SEE, TO YOU WILL I GIVE IT, [AND TO YOUR SEED FOREVER]. The Holy One said to Moses: Although I had agreed with the ancestors to give them the land, and even though they have died, I am not going back on <my word>. Instead (according to Is. 40:8): BUT THE WORD OF OUR GOD SHALL STAND FOR EVER.