Albert Barnes Commentary Habakkuk 3:9

"Thy bow was made quite bare; The oaths to the tribes were a [sure] word. Selah. Thou didst cleave the earth with rivers." — Habakkuk 3:9 (ASV)

Your 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, Kir laid bare the shield (Isaiah 22:6). Gregory, Mor. xix. 9, n. 54; Compare Augustine in Psalms 59:0, n. 6: The bow represents the threat of the vengeance of Almighty God, from which it is finally discharged, if not turned aside; the longer the string is drawn, the sharper issues 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. As long as judgment is delayed, the bow seems laid up in its sheath.

God’s judgments mostly strike suddenly, as with a swift arrow (Psalms 64:7), because men do not regard them, coming from a distant bow that they do not see. His more signal judgments He makes bare in sight of all.

According to the oath to the tribes - This refers to the oath which He swore to our father Abraham, an 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 hidden as long as God did not complete it.

Selah. A pause follows, in which to meditate on all that is contained in the word or promise of God, which is all time and eternity.

You split the earth into rivers - Sea and river had become dry land for the passage 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, many streams issue forth—namely, as many as convey the waters of His teaching to water the earth.