What does Psalm 33:4 mean?

The first two of several reasons for praising the Lord with joy appear in this verse. First, God's Word is true. When Jesus prayed to the Father in His High Priestly Prayer, He asked that believers be sanctified in the truth, adding, "your word is truth" (John 17:17). In his letter to Titus, Paul affirms that God is incapable of lying. He states categorically that God never lies (Titus 1:2). Psalm 119:142 declares that the Lord's law is true, and verse 160 affirms, "The sum of your word is truth."

According to this verse, everything God does is dependable. All the Lord's works are performed in faithfulness. Whatever the Lord does exhibits His unfailing care. This description comes from a Hebrew word which also refers to "trustworthiness" or "honesty." The Lord God makes no mistakes. We may trust Him, therefore, to orchestrate all the events in our lives for our good and His glory (Romans 8:28–30).