What do we learn from "Tzofeh Rasha la'Tzadik u'Mevakesh Hamiso"?
Kidushin 30b: A man's Yetzer overpowers him every day and seeks to destroy him. Without Hashem's help, the Tzadik could not prevail 1 - "Hashem will not abandon (the Tzadik and let him fall) into its hands" (verse 33).
Radak: If a Rasha sees a Tzadik succeed, and [the Rasha] himself falls, he envies him, and seeks a pretext to slander him to the governor to kill him.
Malbim: The Rasha seeks to tilt the Tzadik from the good path and make him sin. He also seeks to kill his body.
Mesilas Yesharim (Perek 2): Man cannot be saved without Hashem's help, for the Yetzer ha'Ra is very strong. If a man oversees himself, then Hashem helps him and he is saved. If he does not oversee himself, 'one who does not have Da'as, it is forbidden to have mercy on him' (Brachos 33a). (I.e. he has Da'as, but does not use it. A true lunatic needs mercy! - PF)
