John Calvin Commentary Deuteronomy 18:12

"For whosoever doeth these things is an abomination unto Jehovah: and because of these abominations Jehovah thy God doth drive them out from before thee." — Deuteronomy 18:12 (ASV)

For all that do these things are an abomination. First, he intends that the authority of God should act as a rein to guide them; then he sets before them the vengeance that they were soon to see inflicted upon the nations—indeed, the vengeance of which they themselves were to be the executioners and ministers.

For since it was beyond all doubt that the inhabitants of the land of Canaan were uprooted from their peaceful dwellings by God’s hand alone, he assigns as the cause of this destruction that they had polluted themselves and their country with these blasphemous and abominable superstitions. By this striking example, then, he deters them from imitating the sins that facts themselves showed were so severely punished. Thus Paul admonishes believers to diligently seek to avoid the sins that provoke God’s wrath against the disobedient (Ephesians 5:6).