Charles Ellicott Commentary Numbers 15:32

"And while the children of Israel were in the wilderness, they found a man gathering sticks upon the sabbath day." — Numbers 15:32 (ASV)

And while the children of Israel were in the wilderness ... — It is better rendered, Now the children of Israel were in the wilderness, and they found, etc. It is probable that the incident recorded here is designed to illustrate the presumptuous sins which were to be punished by death. The offense may have been committed shortly after the promulgation of the commandments contained in this chapter, but all that is certain is that it was committed “in the wilderness,” that is, according to Ibn Ezra, in the wilderness of Sinai, but more probably during the period of the wanderings in the wilderness after the arrival at Kadesh. No inference can be drawn from this verse concerning the time at which the account was committed to writing.

The observance of the Sabbath was obligatory in the wilderness as well as in the land of Canaan , and the punishment of death had already been decreed against those who profaned it by doing any work on it (Exodus 35:2), but the manner in which death was to be inflicted does not appear to have been declared until now. The same verb rendered here as “declared” occurs in the parallel case of the blasphemer in Leviticus 24:12, where it is rendered “shewed”: And they put him in ward, that the mind of the Lord might be shewed them. The punishment of death had already been decreed against those who cursed their father or mother (Leviticus 20:9). It could hardly be thought that a lighter punishment was to be inflicted on one who blasphemed the name of Jehovah; but in that case, as in this, the mode of death does not appear to have been previously prescribed.