"Here now is the man who did not make God his stronghold but trusted in his great wealth and grew strong by destroying others!"
These are the words of verse 7, and the previous 6 verses speak of how the man boasts of evil, who speaks falsehood rather than truth, and how the Lord will bring him to ruin.
What the righteous say of him is not that he was a terrible sinner, nor that he was a liar, though he was. His great fault is that he trusted in his own wealth, his own works, himself, rather than trusting in God. The righteous know that they, too, are liars and sinners, and that it is only by the grace of God that they are saved. Because they know this and understand it, they do not trust in themselves, but in the God's unfailing love and His name.
Do I trust in myself and my own wealth (though not necessarily monetary wealth) or do I make God my stronghold?