The speaker connects with the preceding passage, that many people will come to trust in the Lord. He arrives at a general statement: when you trust in the Lord, you are blessed and considered to be happy. That person does not seek his salvation with proud people. The proud do not seek salvation with the Lord; they think they can take care of themselves, and that is a lie. Therefore, a proud person is trapped in lies. We see two opposites here: to be in awe of the Lord and trusting in him over against seeking your answers with those who are proud, who are, in fact, trapped in Satan’s nets. Briefly put, truth stands over against lies. In the life of David you can think of Saul and his followers, or Absalom and his followers.
In Leviticus we are warned against trusting in spirits: “Do not turn to mediums or necromancers; do not seek them out, and so make yourselves unclean by them: I am the Lord your God” (Leviticus 19:31). And in Ezekiel we are told not to trust the heathen nations, such as Egypt: “And it shall never again be the reliance of the house of Israel, recalling their iniquity, when they turn to them for aid. Then they will know that I am the Lord God” (Ezekiel 29:16).
Over against pride and curses are the blessings from the Lord. Psalm 1:1–2: “Blessed is the man who walks not in the counsel of the wicked…but his delight is in the law of the Lord, and on his law he meditates day and night.” Psalm 32:2: “Blessed is the man against whom the Lord counts no iniquity.” With words come deeds, as in Psalm 41:1 Blessed is the one who considers the poor.
After these beatitudes follows the argumentation in the next verse, Psalm 40:5.
4 Blessed is the man who makes the LORD his trust, who does not turn to the proud, to those who go astray after a lie!