30 Wisdom and knowledge and wise suggestions are of no use against the Lord.

Matthew Henry's Commentary on Proverbs 21:30

Commentary on Proverbs 21:30-31

(Read Proverbs 21:30-31)

Means are to be used, but, after all, our safety and salvation are only of the Lord. In our spiritual warfare we must arm ourselves with the whole armour of God; but our strength must be in the Lord, and in the power of his might.