It was necessary that this sin should be punished, as a testimony to surrounding nations of God’s displeasure against idolatry. By executing justice upon the guilty, Moses, as God’s instrument, must leave on record a solemn and public protest against their crime. As the Israelites should hereafter condemn the idolatry of the neighboring tribes, their enemies would throw back upon them the charge that the people who claimed Jehovah as their God had made a calf and worshiped it in Horeb. Then though compelled to acknowledge the disgraceful truth, Israel could point to the terrible fate of the transgressors, as evidence that their sin had not been sanctioned or excused. (PP 325.1) MC VC

Love no less than justice demanded that for this sin judgment should be inflicted. God is the guardian as well as the sovereign of His people. He cuts off those who are determined upon rebellion, that they may not lead others to ruin. In sparing the life of Cain, God had demonstrated to the universe what would be the result of permitting sin to go unpunished. The influence exerted upon his descendants by his life and teaching led to the state of corruption that demanded the destruction of the whole world by a flood. The history of the antediluvians testifies that long life is not a blessing to the sinner; God’s great forbearance did not repress their wickedness. The longer men lived, the more corrupt they became. (PP 325.2) MC VC

So with the apostasy at Sinai. Unless punishment had been speedily visited upon transgression, the same results would again have been seen. The earth would have become as corrupt as in the days of Noah. Had these transgressors been spared, evils would have followed, greater than resulted from sparing the life of Cain. It was the mercy of God that thousands should suffer, to prevent the necessity of visiting judgments upon millions. In order to save the many, He must punish the few. Furthermore, as the people had cast off their allegiance to God, they had forfeited the divine protection, and, deprived of their defense, the whole nation was exposed to the power of their enemies. Had not the evil been promptly put away, they would soon have fallen a prey to their numerous and powerful foes. It was necessary for the good of Israel, and also as a lesson to all succeeding generations, that crime should be promptly punished. And it was no less a mercy to the sinners themselves that they should be cut short in their evil course. Had their life been spared, the same spirit that led them to rebel against God would have been manifested in hatred and strife among themselves, and they would eventually have destroyed one another. It was in love to the world, in love to Israel, and even to the transgressors, that crime was punished with swift and terrible severity. (PP 325.3) MC VC