Psalms 78:18

18.And they tempted God in their heart. This is the provocation of which mention is made in the preceding verse. Not that it was unlawful for them simply to ask food, when constrained to do so by the cravings of hunger. Who can impute blame to persons, when being hungry, they implore God to supply their necessities? The sin with which the Israelites were chargeable consisted in this, that not content with the food which He had appointed them, they gave loose reins to their lusts. He, at that time, had begun to feed them with manna, as we shall again see by and by. It was their loathing of that sustenance which impelled them eagerly to desire new food, as if they disdained the allowance assigned them by their heavenly Father. This is what is meant when it is said that they asked food for their soul (326) They were not reduced to the necessity of asking it by hunger; but their lust was not satisfied with living on the provision which God had appointed for them. On this account, it is declared, that they tempted God, overpassing, as they did, the bounds within which he had limited them. Whoever, undervaluing and despising the permission or license which He grants, gives full scope to his own intemperate lust, and desires more than is lawful, is said to tempt God. He acts as if he would subject Him to his own caprice, or questioned whether He could do more than he is pleased really to do. God has power to accomplish whatever he wills; and assuredly, the person who would separate the power of God from his will, or represent him as unable to do what he wills, does all he can to rend him in pieces. Those are chargeable with doing this, who are set upon trying whether he will grant more than he has given them permission to ask. That, therefore, the lust of the flesh may not stir us up to tempt him, let us learn to impose a restraint upon our desires, and humbly to rest contented within the limits which are prescribed to us. If the flesh is allowed to indulge itself without control, we will not be satisfied with ordinary bread, but will often, and in many ways, murmur against God.