Charles Ellicott Commentary Deuteronomy 32:22

"For a fire is kindled in mine anger, And burneth unto the lowest Sheol, And devoureth the earth with its increase, And setteth on fire the foundations of the mountains." — Deuteronomy 32:22 (ASV)

For a fire is kindled in my anger. —Quoted by Jeremiah (Jeremiah 15:14, and compare to Jeremiah 17:4).

The foundations of the mountains. —Rashi says, “Jerusalem, which is founded on the mountains,” as it is said, Jerusalem, the mountains are about her (Psalms 125:2).