John 17:21
John 17:2121that all of them may be one, as You, Father, are in Me, and I am in You. May they also be in Us, so that the world may believe that You sent Me.
The Watchtower deploys this verse to argue that the unity Jesus prays for is "unity of purpose" — not ontological unity. Jesus and the Father are unified as a king and his ambassador are unified, by aligned will and common mission, not by shared essence. The unity of the disciples Jesus prays for is therefore taken as the model of organisational unanimity within Jehovah's organisation, with everyone aligned behind the Governing Body's direction.
The verse will not bear the "purpose-only" reading. Jesus describes the disciples' future unity with a comparison: "just as you, Father, are in me and I in you, that they also may be in us." That is mutual indwelling — the Father in the Son, the Son in the Father, and disciples in the Father and Son. Mere alignment of purpose cannot account for the disciples being "in" the Father and Son the way the Father and Son are "in" one another. Pair this with — the Father and Son make their dwelling with the believer — and the perichoretic language of John's farewell discourse comes into focus. The unity Jesus prays for is grounded in the unity he already enjoys with the Father, which is the unity of the divine life itself.
The NWT renders the Greek preposition en ("in") as "in union with" four times in this single verse — "in union with me," "in union with you," "in union with us." The mainstream English versions retain the simpler "in." The expansion is not mistranslation, but it deflects the verse away from mutual indwelling toward relational alignment. JW theology denies ontological unity between Father and Son and reads the unity language here in social terms; the NWT's preposition choice pre-loads the verse for that reading. The same softening recurs at verse 26 ("I in union with them").