John Gill Commentary Leviticus 24:12

"And they put him in ward, that it might be declared unto them at the mouth of Jehovah." — Leviticus 24:12 (ASV)

And they put him in ward

In some prison, a place known in the camp, as Aben Ezra observes: that the mind of the Lord might be shown them ;

For, though this was a breach of the third command, in which God declares he would not hold such a one guiltless (Exodus 20:7), yet no particular punishment being expressed, it was not a clear case whether the Lord would punish for it himself, by an immediate stroke of his hand, or whether by the civil magistrate; and if by the latter, in what manner.

For though it might be concluded, without any hesitation, that he was worthy of death, since cursing father or mother was death (Exodus 21:17, Leviticus 20:9), and much more blaspheming God, yet what death to put him to they might be at a loss about; or if that was understood of stoning, they might think this deserved a more severe punishment, and therefore consulted God about it.