Numbers 21:6

For they that were stung therewith, were so inflamed with the heat thereof, that they died. 1 Cor. 10:9

Fiery serpents. They are so called, because they that were bitten by them were burnt with a violent heat. (Challoner) — Hence they are called seraphim, by which name an order of angels is known. The Egyptians adored a serpent which they called serapis, at Rome; and they represented their god serapis, with a serpent entwining a monstrous figure, composed of a lion, a dog, and a wolf. (Macrob. Saturn i. 20.) The seraph was a winged serpent, Isaias xiv. 29. xxx. 6. Such often infested Egypt, in spring, coming from Arabia, unless they were intercepted by the ibis. Their wings resembled those of bats. (Herodotus, ii. 76.; Mela, &c.) God probably sent some of this description into the camp of the Israelites. (Calmet) — Some call them prœster, (Pliny, [Natural History?] xxiv. 13,) from their burning; others the hydra, or, when out of water, the chershydra, the venom of which is most dangerous. The Septuagint style them simply, “the destroying, or deadly serpents.” See Bochart, T. ii. B. iii. 13.; Deuteronomy viii. 15.; Wisdom xvi. 5, 10.) (Haydock)

III. The righteous judgment which God brought upon them for their murmuring, v. 6. He sent fiery serpents among them, which bit or stung many of them to death. The wilderness through which they had passed was all along infested with those fiery serpents, as appears, Deut 8 15. But hitherto God had wonderfully preserved his people from receiving hurt by them, till now that they murmured, to chastise them for which these animals, which hitherto had shunned their camp, now invade it. Justly are those made to feel God's judgments that are not thankful for his mercies. These serpents are called fiery, from their colour, or from their rage, or from the effects of their bitings, inflaming the body, putting it immediately into a high fever, scorching it with an insatiable thirst. They had unjustly complained for want of water (v. 5), to chastise them for which God sends upon them this thirst, which no water would quench. Those that cry without cause have justly cause given them to cry out. They distrustfully concluded that they must die in the wilderness, and God took them at their word, chose their delusions, and brought their unbelieving fears upon them; many of them did die. They had impudently flown in the face of God himself, and the poison of asps was under their lips, and now these fiery serpents (which, it should seem, were flying serpents, Isa 14 29) flew in their faces and poisoned them. They in their pride had lifted themselves up against God and Moses, and now God humbled and mortified them, by making these despicable animals a plague to them. That artillery is now turned against them which had formerly been made use of in their defence against the Egyptians. He that brought quails to feast them let them know that he could bring serpents to bite them; the whole creation is at war with those that are in arms against God.

Verses 4-9 The children of Israel were wearied by a long march round the land of Edom. They speak discontentedly of what God had done for them, and distrustfully of what he would do. What will they be pleased with, whom manna will not please? Let not the contempt which some cast on the word of God, make us value it less. It is the bread of life, substantial bread, and will nourish those who by faith feed upon it, to eternal life, whoever may call it light bread. We see the righteous judgment God brought upon them for murmuring. He sent fiery serpents among them, which bit or stung many to death. It is to be feared that they would not have owned the sin, if they had not felt the smart; but they relent under the rod. And God made a wonderful provision for their relief. The Jews themselves say it was not the sight of the brazen serpent that cured; but in looking up to it, they looked up to God as the Lord that healed them. There was much gospel in this. Our Saviour declared, ( john 3:14 john 3:15 ) , that as Moses lifted up the serpent in the wilderness, so the Son of man must be lifted up, that whatsoever believeth in him, should not perish. Compare their disease and ours. Sin bites like a serpent, and stings like an adder. Compare the application of their remedy and ours. They looked and lived, and we, if we believe, shall not perish. It is by faith that we look unto Jesus, ( Hebrews 12:2 ) . Whosoever looked, however desperate his case, or feeble his sight, or distant his place, was certainly and perfectly cured. The Lord can relieve us from dangers and distresses, by means which human reason never would have devised. Oh that the venom of the old serpent, inflaming men's passions, and causing them to commit sins which end in their eternal destruction, were as sensibly…