Psalms 72:3 - Matthew Poole's English Annotations on the Holy Bible

He mentioneth the mountains and hills, as bringing forth this blessed fruit; either because such places are usually barren, and therefore this was an evidence of extraordinary fruitfulness, and a special blessing of God; or because they are dangerous to passengers, in regard of the robbers and wild beasts, which commonly abide there; whereby it is implied that other places should do so too, and that it should be common and universal. Peace; all manner of prosperity and felicity, which the Hebrews frequently express by that word.