Notice the words peace and upright parallel blameless. Surely the mind and heart of man are cunning. The man who is attacked in this context is just a hapless traveler who fell into the clutches of wicked men. He is just in the sense he does not deserve this assault. In modern terms an innocent victim.
Bloodthirsty men hate a man of integrity and seek to kill the upright.
But the upright are concerned for his life. My locks with the damp of the night. The husband speaking to the wife the language of love in which perfection is that of beauty.