Charles Ellicott Commentary Psalms 95:4

"In his hand are the deep places of the earth; The heights of the mountains are his also." — Psalms 95:4 (ASV)

Deep places. —From a root meaning “to search,” perhaps by digging. Thus, either “mines” or “mineral wealth.”

Strength of the hills. —The Hebrew word rendered “strength” is rare, found only here and in Numbers 23:22; Numbers 24:8 (strength of an unicorn), and Job 22:25 (plenty of silver; margin, silver of strength). The root to which the word is usually assigned means “to be weary,” from which the idea of strength can only be derived on the lucus a non lucendo principle. Keeping the usual derivation, we may, with many critics, give the word the sense of “mines” or “treasures,” because of the labors of extracting metal from the earth. This suits Job 22:25 and makes a good parallelism. But the Septuagint and Vulgate have “heights,” and by another derivation, the Hebrew may mean shining, and so “sunny summit.” This agrees with the rendering of the Septuagint in Numbers 23:22; Numbers 24:8, and the rhythm is preserved by an antithetic parallelism, as in the next verse.