Shared ground
Psalm 64:5–6 portrays wrongdoing as deliberate and cooperative, not accidental. The opponents strengthen each other in “evil plans,” talk through the details, and keep the traps hidden. Their confidence is part of the problem: they say, “Who will see them?”—acting as if secrecy removes accountability.
The text also links outward harm to inner life. It ends by saying the human “mind and heart” can be cunning, suggesting that harmful action often comes from skilled, inward strategizing rather than a momentary impulse.
Where interpretation differs
Some readers take “Who will see them?” mainly as confidence that other people (neighbors, victims, leaders, courts) will not detect the scheme. Others hear a deeper arrogance: the plotters speak as if even God will not notice or respond.
Some also read the final line (“man’s mind and heart are cunning”) as a general statement about humanity’s capacity for crafty wrongdoing. Others take it more narrowly as a diagnosis of these particular enemies.
Why the disagreement exists
The poem reports the enemies’ speech without specifying whom they think is blind (people, authorities, or God). Likewise, the shift from describing “they” to a statement about “man” can sound either like a general conclusion or a pointed summary of the group just described.
What this passage clearly contributes
Explicitly, the passage claims that evildoers can reinforce each other, plan hidden traps, and feel secure because they expect to remain unseen; it also calls their aim “injustice” and notes their pride in a “perfect” (thorough) plan. By inference, it presents secrecy and self-congratulation as features of calculated harm, and it connects such harm to the skilled use of human thought and desire—“mind and heart”—in devising it (compare the psalm’s earlier focus on hidden attacks and speech in Psalm 64:1–4).