When He adds, I pray not for the world, by the world He means those who live according to the lust of the world, and have not the lot to be chosen by grace out of the world, as those had for whom He prayed: But for them which Thou hast given Me. It was because the Father had given Him them, that they did not belong to the world. Nor yet had the Father, in giving them to the Son, lost what He had given: For they are Thine.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).
Also cites: Tr. cvi