What does Psalm 58:4 mean?

In the prior verse (Psalm 58:3), David accused certain human authorities (Psalm 58:1–2) of being purposefully wicked. Not only were these men plotting evil, and causing violence, but they were opposed to truth. Their words were lies, but they also made a deliberate effort to ignore what was true, including the will of God. Here, David begins an analogy that captures how insidious this attitude can be. Scripture sometimes compares lies and slander to poison and venom (Psalm 140:1–3; Romans 3:13). A cobra's mouth delivers a venomous bite causing death: a liar delivers poisonous slander causing harm. During the era of Saul (1 Samuel 19:1–2; 20:32–33), it's likely his officials said many untrue, evil things about David.

The wicked rulers and judges of Israel did not merely resemble poisonous snakes, such as cobras and adders, but "deaf" serpents. Even worse, this was deliberate deafness. A snake-charmer (Psalm 58:5) plays music to give the impression that he is mesmerizing a snake to stand up and dance. The illusion of snake-charming suggests that the snake listens to the charmer's music and avoids biting. What truly happens is a simple defense mechanism, since snakes perceive sounds differently than humans. David depicts the unjust judges as deadly snakes who metaphorically plug their own ears to ignore the music and lash out with poison.

Vicious lies and hardened sin are characteristics of those still belonging to Satan, whom Jesus described as not standing in the truth. He said "there is no truth in him. When he lies, he speaks out of his own character, for he is a liar and the father of lies" (John 8:44). When the Devil tempted Eve, appearing as a serpent (Revelation 20:2), he lied about what God had said. God had told Adam and Eve: "Of the tree of the knowledge of good and evil you shall not eat, for in the day that you eat of it you shall surely die" (Genesis 2:17). "But the serpent said to the woman, 'You will not surely die'" (Genesis 3:4).