Contradiction with Psalm 33:16-17
These verses emphasize that a mighty army or a strong horse does not guarantee victory, thus contradicting Proverbs 21:31, which suggests preparation is essential for victory.
Psalm 33:16-17: There is no king saved by the multitude of an host: a mighty man is not delivered by much strength.
Contradiction with Ecclesiastes 9:11
This verse points out that the race is not always to the swift nor the battle to the strong, implying that outcomes are not always determined by preparation or might, in contrast to Proverbs 21:31.
Ecclesiastes 9:11: I returned, and saw under the sun, that the race [is] not to the swift, nor the battle to the strong, neither yet bread to the wise, nor yet riches to men of understanding, nor yet favour to men of skill; but time and chance happeneth to them all.
Contradiction with 1 Samuel 17:47
This verse conveys that the Lord saves not with sword and spear, for the battle is the Lord's, contradicting the notion in Proverbs 21:31 that preparation for battle leads to victory.
1 Samuel 17:47: And all this assembly shall know that the LORD saveth not with sword and spear: for the battle [is] the LORD'S, and he will give you into our hands.