Jews today say that they don't accept Jesus as the Jewish Messiah because He didn't fulfill the Messianic prophecies that He would deliver Israel from all oppression and bring peace on earth.
What we are waiting for Jesus to fulfill in his second coming, unbelieving Jews say Jesus should have fulfilled in His first coming.
That's a, more-or-less, Dispensationalist perspective. Mainstream Christian teaching would be that Jesus really did accomplish that Messianic mission, it's just that it was fulfilled in a bigger and deeper way than what was expected. Jesus isn't going to return to sit on David's throne, Jesus already is King Messiah, the son of David, reigning as King not only over Israel, but of the whole cosmos--when the Lord returns, He returns as Judge of the living and the dead, the dead are raised, and there will be the restoration of all things--the renewal of all creation.
But the mystery of the kingdom is that it is both now and not yet. The kingdom is not something we wait around to see, it "does not come with observation" Jesus tells us. Jesus, as the Lord Christ, really has inaugurated God's reign as the Messiah, His death, resurrection, and ascension are all part of His royal, Messianic work.
Consider: Israel begged God for a king, but Israel needed no king because God was Israel's king. Nevertheless, God agreed and let Samuel choose Saul. The example of Saul shows us the futility of earthly kings and kingdoms. But to the house of David was promised an everlasting throne, and in Christ we see that the everlasting throne of David's house was not for a temporal kingdom, but the everlasting kingdom of the Son of Man, lifted up before the Ancient of Days and given all power and dominion (Daniel 7:13-14), "All authority in heaven and on earth has been given to Me" (Matthew 28::18). The kingdom is now and not yet, it is now, here, Christ's reign through His Church in the Church's sacred mission and vocation to the world as the Body of Christ; and it is not yet, for we look forward in hopeful anticipation of what awaits us at the Eschaton, in the glorious world of God's future.
It is precisely in this tension between that now and not yet that our Christian lives are found here and now. Having received already what is promised for the future, through faith. Our justification, our present salvation, is the working of the power of God's grace bringing that future life into the present: This is why we can point to our baptism that we have been "raised with Christ" to "newness of life" because we have been united to Him in His death and burial; thus we have have the firstfruits of the resurrection Jesus who by the Holy Spirit gives life to us who were "dead in our trespasses" and has already seated us "in heavenly places with Christ Jesus" (Ephesians 2:5-6).
Our prayer, as Christ our Lord taught us to pray, is "Your kingdom come".
The direction of God's activity is always downward--God comes down. To enter the kingdom is not about going someplace else, but about being part of God's kingdom project in the world, by the energizing and quickening power of the Holy Spirit.
If we are rightly understanding the Eucharist, then we rightly understand God in Christ in us by the power of the Spirit; for what we receive in the Eucharist is what we then proclaim and bring the world: Christ and the saving power of His Gospel, His own life, death, and resurrection. For here Christ is, flesh and blood, given for us; and here by this Communion Christ and Church together, and Christ in the Church, and Christ for the world through the Church. Men try to make the kingdom happen by violence, but they do not find it. Because the kingdom cannot be found in violence, it can only be found in the humble and victorious Lamb of God--the Lamb who alone is worthy to open the seal, the Lamb who is the Temple of God in the New Jerusalem, the Light of the world, the Word of God, the only-begotten Son, Jesus Christ our Lord.
Those who seek for earthly kingdoms and earthly powers will not be satisfied. Because the everlasting kingdom of God is not power and sword, but weakness and the cross,
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You know that the rulers of the nations lord it over them, and their superiors exercise authority over them. It shall not be this way among you. Instead, whoever wants to become great among you must be your servant, and whoever wants to be chief among you must be your slave--just as the Son of Man did not come to be served, but to serve, and to give His life as a ransom for many." - Matthew 20:26-28
The Greatest in the kingdom is Himself Servant of all.
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Out of the anguish of his soul he shall see and be satisfied; by his knowledge shall the righteous one, my servant, make many to be accounted righteous, and he shall bear their iniquities." - Isaiah 53:11
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I tell you, among those born of women none is greater than John. Yet the one who is least in the kingdom of God is greater than he" - Luke 7:28
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Have this mind among yourselves, which is yours in Christ Jesus, who, though he was in the form of God, did not count equality with God a thing to be grasped, but emptied himself, by taking the form of a servant, being born in the likeness of men. And being found in human form, he humbled himself by becoming obedient to the point of death, even death on a cross. Therefore God has highly exalted him and bestowed on him the name that is above every name, so that at the name of Jesus every knee should bow, in heaven and on earth and under the earth, and every tongue confess that Jesus Christ is Lord, to the glory of God the Father." - Philippians 2:5-11
-CryptoLutheran