Charles Ellicott Commentary Job 20:17

"He shall not look upon the rivers, The flowing streams of honey and butter." — Job 20:17 (ASV)

The brooks of honey and butter. —He uses language that might suggest he was familiar with the promise of Canaan. However, since the phrase is not precisely identical, it could instead indicate a shared body of proverbial language, and perhaps also that the expression land flowing with milk and honey was already a common saying and did not originate with the Pentateuch.