Numbers 21:5

Meaning, Manna, which they thought did not nourish. Num. 11:6

God. They had before often directed their complaints against the two brothers. Now, Aaron being no more, they attack God himself, who had always resented the injury done to his ministers. — Food. So they call the heavenly manna: thus worldlings loathe the things of heaven, for which they have no relish. (Challoner) — Septuagint, “our soul is indignant at this most empty bread,” which has no solidity in it, nor support. Many translate the Hebrew, “most vile bread.” Thus, in the blessed eucharist, the substance of bread is removed, and the accidents only appear; so that to the worldly receiver, it seems very empty and light, though in reality it be supersubstantial; containing Christ himself, who fills the worthy communicant with grace and comfort, and enables him to go forward, on the road to heaven, without fainting. (Haydock)

II. Their unbelief and murmuring upon this occasion, v. 5. Though they had just now obtained a glorious victory over the Canaanites, and were going on conquering and to conquer, yet they speak very discontentedly of what God had done for them and distrustfully of what he would do, vexed that they were brought out of Egypt, that they had not bread and water as other people had by their own care and industry, but by miracle, they knew not how. They have bread enough and to spare; and yet they complain there is no bread, because, though they eat angels' food, yet they are weary of it; manna itself is loathed, and called light bread, fit for children, not for men and soldiers. What will those be pleased with whom manna will not please? Those that are disposed to quarrel will find fault where there is no fault to be found. Thus those who have long enjoyed the means of grace are apt to surfeit even on the heavenly manna, and to call it light bread. But let not the contempt which some cast upon the word of God cause us to value it the less: it is the bread of life, substantial bread, and will nourish those who by faith feed upon it to eternal life, whoever calls it light bread.

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…