Proverbs 21:31. The horse is prepared, &c. — Under which particular all warlike preparations are comprehended; but safety is of the Lord — The success of the battle depends not upon any human strength or art, but upon God’s providence, who gives the victory when and to whom he pleases, and frequently to those that have least reason to expect it.

The prior proverb noted, broadly, that no human effort could possibly undo God's intended purposes. This verse underscores the Lord's sovereign control of history. A nation may mount an impressive arsenal of weapons, but victory does not depend exclusively upon weapons. God's will is infinitely more powerful and is ultimately all that matters.