Mujahid said, "This also refers to idols and the True God, may He be exalted." Meaning that the idol is dumb and cannot speak or say anything, good or otherwise. It cannot do anything at all, no words, no action, it is dependent and is a burden on its master.
(whichever way he directs him,) meaning, wherever he sends him
(he brings no good.) meaning, he does not succeed in what he wants.
(Is such a man equal) meaning, a man who has these attributes
(to one who commands justice) meaning fairness, one whose words are true and whose deeds are righteous.
(and is himself on the straight path) Al-`Awfi reported that Ibn `Abbas said: "This is also an example of the disbeliever and the believer", as in the previous Ayah.