Jesus’ answer was that the kingdom of God was not coming in the manner the Pharisees were expecting. The kingdom would not be inaugurated with spectacle or splendor; there would be no great and magnificent leader who staked out a geographical claim and routed the Romans; rather, the kingdom would come silently and unseen, much as leaven works in a batch of dough (see Matthew 13:33). In fact, Jesus says, the kingdom had already begun, right under the Pharisees’ noses. God was ruling in the hearts of some people, and the King Himself was standing among them, although the Pharisees were oblivious to that fact.
Various translations render the Greek of Luke 17:21 various ways. The phrase translated “within you” in the KJV and NKJV is translated as “in your midst” in the NIV, NASB, and NET; “among you” in the NLT and HCSB; and “in the midst of you” in the ESV. Earlier versions of the NIV had “within you” with a marginal note suggesting “among you.” There is obviously a difference between saying “the kingdom of God is within you” and “the kingdom of God is among you.”
“Within you” comes off as an unfavorable translation, seeing that Jesus was speaking to the Pharisees at the time. Jesus was surely not saying that the kingdom of God resided within the Pharisees’ hearts. The Pharisees opposed Jesus and had no relationship with God. Jesus in other places denounced them as “whitewashed tombs” and “hypocrites” (Matthew 23:27).
The better translation would be “in your midst” or “among you.” Jesus was telling the Pharisees that He brought the kingdom of God to earth. Jesus’ presence in their midst gave them a taste of the kingdom life, as attested by the miracles that Jesus performed. Elsewhere, Jesus mentions His miracles as definitive proof of the kingdom: “If I drive out demons by the finger of God, then the kingdom of God has come upon you” (Luke 11:20).
There are three popular interpretations of Jesus’ words in Luke 17:21 that the kingdom of God is within you (or among you): 1) the kingdom of God is essentially inward, within man’s heart; 2) the kingdom is within your reach if you make the right choices; and 3) the kingdom of God is in your midst in the person and presence of Jesus. The best of these interpretations, it seems, is the third: Jesus was inaugurating the kingdom as He changed the hearts of men, one at a time.
For the time being, Christ’s kingdom is not of this world (John 18:36). One day, however, the kingdom of God will be manifest on the earth (Isaiah 35:1), and Jesus Christ will rule a physical kingdom from David’s throne (Isaiah 9:7) with Jerusalem as His capital (Zechariah 8:3).