7 Nevertheless I tell you the truth; It is expedient for you that I go away: for if I go not away, the Comforter will not come unto you; but if I depart, I will send him unto you. 8 And when he is come, he will reprove the world of sin, and of righteousness, and of judgment:
9 Of sin, because they believe not on me;
10 Of righteousness, because I go to my Father, and ye see me no more;
11 Of judgment, because the prince of this world is judged.
OF JUDGMENT: Satan is the prince and the power of the air (Ephesians 2:2). He is the spirit that now worketh in the children of disobedience (The world which lives in unbelief). The devil will be judged and anyone who follows the course of this world will be judged with him.
“Then shall he say also unto them on the left hand, depart from me, ye cursed, into everlasting fire, prepared for the devil and his angels” Matthew 25:41
God poured out His Judgement on Calvary when His Son was crucified on the cross so we could have mercy.
If you refuse to turn from the course of this world you too will go into the lake of fire with the devil.