A.T. Robertson Commentary John 17:14

"I have given them thy word; and the world hated them, because they are not of the world, even as I am not of the world." — John 17:14 (ASV)

Not of the world (ουκ εκ του κοσμου). They are "in the world" (εν τω κοσμω, verse 13) still and Christ sends them "into the world" (εις τον κοσμον, verse 18), but they must not be like the world nor get their spirit, standards, and message "out of the world," else they can do the world no good. These verses (14-19) picture the Master's ideal for believers and go far towards explaining the failure of Christians in winning the world to Christ. Too often the world fails to see the difference or the gain by the change.