Leviticus 24:13-14

That all the congregation should engage in the punishment was no doubt meant to convey the idea how dreadful the sin was. And moreover, it tended, under divine grace, to keep others from such daring presumption. For who that had joined in stoning another for blasphemy, at the command of GOD, could himself hope to escape, if afterwards found guilty of it? That is a suitable prayer of the Psalmist, Psalms 19:13.