Thy bow was made quite naked - The word is repeated for emphasis. Literally, (In) “nakedness, it was laid naked;” the sheath being laid aside and cast away, as Isaiah says, Isaiah 22:6. “Kir laid bare the shield.” Gregory, Mor. xix. 9. n. 54, Compare Augustine in Psalms 59, n. 6.: The bow represents the threat of the vengeance of Almighty God, from which it is at length discharged, if not turned aside; the longer the string is drawn, the sharper issueth the arrow. So then the more the coming of the day of judgment is delayed, the stricter is the severity of the judgment then issuing. So long as judgment is delayed, the bow seems laid up in its sheath. God’s judgments mostly strike suddenly. Psalms 64:7, “as with a swift arrow,” because men regard them not, coming from a bow at a distance which they see not. His more signal judgments He makes bare in sight of all.
According to the oath of (to) the tribes - “the oath which He swore unto our father Abraham,” which oath He often renewed to Abraham, Isaac and Jacob, and again to David This oath, the word and promise of God, was the pledge of the deliverance of His people, that they “should be saved from their enemies, and from the hand of all that hate them.” It lay, as it were, covered and hid, so long as God completed it not. Selah. A pause followeth, wherein to meditate on all which is contained in the word or promise of God, which is all time and eternity.
Thou didst cleave the earth with (into) rivers - Sea and river had become dry land for the passing through of God’s people; again, the rock, struck by Moses’ rod, was split, so that “rivers ran in the dry places.” Until that Rock, which was Christ, was stricken, and “out of His side came blood and water” John 19:24, the whole world was desert and barren; then it was turned into streams of water, and “now not four but twelve streams went forth from the Paradise of Scriptures” (Jerome) For from the One Fountain which is Christ, there issue many streams, even as many as convey the waters of His teaching, to water the earth.