John Gill Bible Commentary

And the Lord said unto Moses,.... Out of the pillar of cloud: behold, thou shalt sleep with thy fathers; a phrase expressive of death, frequently used both of good and bad men, which serves to render death easy and familiar, and less formidable; and to assure and lead into an expectation of an awaking out of it, or a resurrection from it: and this people will rise up; in their posterity; for not till after Joshua's death, and the death of the elders of Israel, did they revolt to idolatry, Jos 24:31, and go a whoring after the gods of the strangers of the land, whither they go to be amongst them; that is, after the gods of the Canaanites, who though at this time the inhabitants of the land, yet when the children of Israel became possessors of it, they were the strangers of it; and being suffered to continue contrary to the directions God had given to destroy them, would be a means of drawing them into the worship of their idols, expressed here by going a whoring after them, or committing whoredom with them. Idolatry in Scripture is frequently signified by fornication and adultery; and, as foretold, this was the case; see Psa 106:35, and will forsake me: their husband, departing from his worship and service: and break my covenant which I have made with them at Sinai; and now again in the plains of Moab, and which had the nature of a matrimonial contract; see Jer 31:32.