Why Israel Must Not Murmur Against Its Creator at Rephidim

Another interpretation of (Genesis 27:22): "THE VOICE IS THE VOICE OF JACOB, but the hands are the hands of Esau." He said to him: Your brother Esau, if troubles reach him, begins to revile and to blaspheme; but you, if sufferings reach you, subdue your impulse and do not, with your voice, provoke your Creator to anger. And if you prattle with your voice, behold, the hands of Esau are groping about you; [but if not, "the voice is the voice of Jacob." What is the meaning of "but the hands are the hands of Esau"?] For thus you find at Rephidim: Israel prattled with their voice and said, "Is the LORD in our midst or not?" (Exodus 17:7), and immediately Amalek came upon them, as it is said, "Then Amalek came" (Exodus 17:8).