Midrash su Salmi 78:19

Rabban Gamaliel said: Israel also slandered the Holy One, blessed be He, (by) saying: Wilt thou say that He has power to feed us in the wilderness? as it is said, "Yea, they spake against God; they said, Can God prepare a table in the wilderness? Behold, he smote the rock, that waters gushed out, and streams overflowed" (Ps. 78:19, 20). The Holy One, blessed be He, heard that they slandered His Glory, || and from His Glory, which is a consuming fire, He sent against them a fire which consumed them round about, as it is said, "And the people were as murmurers… and the fire of the Lord burnt among them, and devoured in the uttermost part of the camp" (Num. 11:1). The Israelites betook themselves to our teacher Moses, and they said to him: Moses, our lord! Let these be given like sheep to the slaughter, but not to the fire which is consuming fire. Moses saw the plight of Israel, and he arose to pray on their behalf, and He was entreated of him, as it is said, "And the people cried unto Moses" (Num. 11:2).