That they all may be one; as thou, Father, art in me, and I in thee, that they also may be one in us: that the world may believe that thou hast sent me.

JOHN 17:21KJV
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John 17:21 (KJV)

What does John 17:21 mean?

John 17:21 records Jesus asking his Father to bring his followers into a shared life with them. Jesus connects that unity with a purpose beyond the group: that the world may believe the Father sent him.

The words “as thou, Father, art in me, and I in thee” picture a close mutual relationship. Jesus is praying not only for those with him then, but also for those who would come to believe through their message, as verse 20 shows.

The Greek behind John 17:21

  • “one” — ἕν (hen): The Greek word means “one” and takes a form that points to oneness rather than to one person. Jesus uses the word for the shared unity he asks for among many people.
  • “world” — κόσμος (kosmos): The Greek word can refer to the world or the people in it. Here the world is the wider audience Jesus hopes will believe the Father sent him.
  • “sent” — ἀποστέλλω (apostellō): The Greek word means to send someone. In this verse, Jesus describes his coming as something the Father directed.

Why John 17:21 matters

  • The unity Jesus requests reaches beyond his immediate companions. His prayer includes future believers who will hear their message, according to verse 20.
  • Jesus connects the followers’ unity with the Father and himself. The phrase “in us” places their shared life within that relationship.
  • Jesus gives the unity a purpose that reaches outward. The words “that the world may believe” connect the request to people beyond those already following him.

Where else these words appear

“be” Greek G5600 · used in 62 verses

  • Matthew 6:4 That thine alms may be in secret: and thy Father which seeth in secret himself shall reward thee openly.
  • John 17:19 And for their sakes I sanctify myself, that they also might be sanctified through the truth.
  • 2 Corinthians 1:17 When I therefore was thus minded, did I use lightness? or the things that I purpose, do I purpose according to the flesh, that with me there should be yea yea, and nay nay?

“I” Greek G2504 · used in 68 verses

  • Matthew 2:8 And he sent them to Bethlehem, and said, Go and search diligently for the young child; and when ye have found him, bring me word again, that I may come and worship him also.
  • John 10:15 As the Father knoweth me, even so know I the Father: and I lay down my life for the sheep.
  • 1 Corinthians 7:40 But she is happier if she so abide, after my judgment: and I think also that I have the Spirit of God.

“me” Greek G1698 · used in 87 verses

  • Matthew 10:32 Whosoever therefore shall confess me before men, him will I confess also before my Father which is in heaven.
  • John 15:5 I am the vine, ye are the branches: He that abideth in me, and I in him, the same bringeth forth much fruit: for without me ye can do nothing.
  • 2 Corinthians 11:10 As the truth of Christ is in me, no man shall stop me of this boasting in the regions of Achaia.

“sent” Greek G649 · used in 130 verses

  • Matthew 2:16 Then Herod, when he saw that he was mocked of the wise men, was exceeding wroth, and sent forth, and slew all the children that were in Bethlehem, and in all the coasts thereof, from two years old and under, according to the time which he had diligently enquired of the wise men.
  • Luke 4:18 The Spirit of the Lord is upon me, because he hath anointed me to preach the gospel to the poor; he hath sent me to heal the brokenhearted, to preach deliverance to the captives, and recovering of sight to the blind, to set at liberty them that are bruised,
  • John 17:8 For I have given unto them the words which thou gavest me; and they have received them, and have known surely that I came out from thee, and they have believed that thou didst send me.