A.T. Robertson Commentary John 16:33

"These things have I spoken unto you, that in me ye may have peace. In the world ye have tribulation: but be of good cheer; I have overcome the world." — John 16:33 (ASV)

That in me ye may have peace (ινα εν εμο ειρηνην εχητε). Present active subjunctive of εχω, "that ye may keep on having peace in me," even when I am put to death, peace to be found nowhere save in me (14:27).

Be of good cheer (θαρσειτε). Imperative active from θαρσος, courage (Acts 28:15). A word for courage in the face of danger, only here in John, but see Mt 9:2,22; Mr 10:49.

I have overcome the world (εγω, νενικηκα τον κοσμον). Perfect active indicative of νικαω, to be victorious, to conquer. Always of spiritual victory in the N.T. See 1 John 5:4f. This majestic proclamation of victory over death may be compared with τετελεστα (It is finished ) in Joh 19:30 as Christ died and with Paul's υπερνικωμεν (we are more than conquerors) in Ro 8:37.