Albert Barnes Commentary Proverbs 21:22

"A wise man scaleth the city of the mighty, And bringeth down the strength of the confidence thereof." — Proverbs 21:22 (ASV)

Even in war, counsel does more than brute strength. So it is with the warfare which is carried on in the inner battlefield of the soul. There also wisdom is mighty to the pulling down of strongholds (2 Corinthians 10:4, where Paul uses the very words of the Septuagint Version of this passage), and the wise man scales and keeps the city which the strong man armed has seized and made his own.