Мидраш к Берешит 9:13

And God remembered Noah (Gen. 8:1). May it please our master to teach us the benediction recited upon witnessing a rainbow. Thus did our masters teach us: Upon seeing a rainbow, one should recite the benediction: Blessed art Thou, O Lord our God, King of the universe, who doth remember His covenant, is faithful in His covenant, and fulfills His word. This blessing is found in the Mishnah.¹²Actually it is found in Berakhot 59b and not in the Mishnah. How do we know that it is also derived from the Torah? Because it is written: I have set My bow in the cloud, and it shall be as a sign of a covenant (Gen. 9:13).

(Gen. 8:1:) THEN GOD REMEMBERED NOAH. [Let our master instruct us: In the case of one who sees the bow in the clouds, what blessing must he say?²⁵Tanh., Gen. 2:6. Thus] have our masters taught: One who sees a bow in the clouds must say a blessing. What blessing does he say? Blessed be the one who remembers the covenant, is trustworthy in his covenant, and has stood by his word. This is from the Mishnah,²⁶Actually the blessing is found, not in the Mishnah, but in the gemara, Ber. 59a. but where is it shown from the Torah? The text reads (in Gen. 9:13): I HAVE SET MY BOW IN THE CLOUD, AND IT SHALL BE A SIGN OF A COVENANT < BETWEEN ME AND THE EARTH >. The conduct of the Holy One is not like the conduct of flesh and blood. In what respect? With flesh and blood, as long as one's close friend is alive, love has its place; and if one dies, love ceases. The Holy One, however, is not like that. When Abraham died, his (the Holy One's) love was preserved for his son Isaac, as stated (in Gen. 25:11): AND IT CAME TO PASS AFTER THE DEATH OF ABRAHAM THAT GOD BLESSED HIS SON ISAAC.

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