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 (John 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 Matthew 9:2; Matthew 9:22; Mark 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 5:4. This majestic proclamation of victory over death may be compared with τετελεστα ( It is finished ) in John 19:30 as Christ died and with Paul's υπερνικωμεν (we are more than conquerors) in Romans 8:37.