John 16:33

33. In me… in the world Here is a striking antithesis. The apostles were in the world; happy if they were in me. They could be in the world and in me at the same time. At the same time, therefore, they could be both in tribulation and in peace. Such men have a right and a reason to be of good cheer. No tribulation from the world can destroy their peace in Christ. And this imperturbable peace is all earnest of the final triumph over the world, announced in the words that follow. Indeed, the bidding of cheer is in view of this closing triumphal sentence.

I have overcome the world Even in view of the coming sacrifice the glorious victim feels himself the conqueror, and chants his paean of victory. Though the battle is yet to be fought, he stands in spirit at its close, and the immortal laurel is upon his brow. Nay, he is standing in spirit in that future period when his apostles, amid tribulation in the world, shall hear in spirit his thrilling words, Be of good cheer; I have overcome the world. And in all ages of the Church the preacher, the martyr, and the saint have fought the battle of the faith, trusting in the great Captain who has overcome the world. And in that trust they too shall overcome. And this victory is over every means which the world uses to deprave the spirit or destroy the soul. Whether the world would allure and ensnare us by its charms, or overwhelm and destroy us by its violence, through faith in Him who has overcome the world we too may overcome.