17:11 keep. Beginning in this verse, the Lord makes five wonderful petitions for His disciples. These are: (1) security in salvation (John 17:11); (2) victory over Satan’s temptations (John 17:15); (3) sanctification through the Word (John 17:17); (4) unity with God and each other (John 17:21); and (5) ultimate glorification with God in heaven (John 17:24). The Father had already promised the Son that not one whom He had given the Son would be lost (John 6:37-39), and we are now given still further assurance through this prayer. The Father will certainly answer the prayer of the Son!
17:15 from the evil. We are to be in the world, but not of the world. “The evil” is “the evil one”—that is, “the prince of this world,” Satan. Because of this prayer of Christ, no doubt, “he that is begotten of God keepeth himself, and that wicked one toucheth him not” (I John 5:18).
17:16 not of the world. We are now, because of Christ, citizens of His world, rather than this world (note Philippians 3:20). We now serve in this world as “ambassadors for Christ” (II Corinthians 5:20).