Have you studied Romans?
Romans 11:25-32
25 For I do not want you, brethren, to be uninformed of this mystery, lest you be wise in your own estimation, that a partial hardening has happened to Israel until the fulness of the Gentiles has come in; 26 and thus all Israel will be saved; just as it is written,
"The Deliverer will come from Zion,
He will remove ungodliness from Jacob."
27 "And this is My covenant with them,
When I take away their sins."
28 From the standpoint of the gospel they are enemies for your sake, but from the standpoint of God's choice they are beloved for the sake of the fathers; 29 for the gifts and the calling of God are irrevocable. 30 For just as you once were disobedient to God, but now have been shown mercy because of their disobedience, 31 so these also now have been disobedient, in order that because of the mercy shown to you they also may now be shown mercy. 32 For God has shut up all in disobedience that He might show mercy to all.
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Or how about Luke:
Luke 21:29-36
29 And He told them a parable: "Behold the fig tree and all the trees; 30 as soon as they put forth leaves, you see it and know for yourselves that summer is now near. 31 "Even so you, too, when you see these things happening, recognize that the kingdom of God is near. 32 "Truly I say to you, this generation will not pass away until all things take place. 33 "Heaven and earth will pass away, but My words will not pass away.
34 "Be on guard, that your hearts may not be weighted down with dissipation and drunkenness and the worries of life, and that day come on you suddenly like a trap; 35 for it will come upon all those who dwell on the face of all the earth. 36 "But keep on the alert at all times, praying in order that you may have strength to escape all these things that are about to take place, and to stand before the Son of Man."
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Tell me Rome, how long is a generation? You see Rome although Jesus does not know the day or the hour (God is omniscient and Jesus is not), he gave us signs of when he would return.
Your appeal to Zechariah 9 is taken out of context:
Zechariah 9:11-13
11 As for you also, because of the blood of My covenant with you,
I have set your prisoners free from the waterless pit.
12 Return to the stronghold, O prisoners who have the hope;
This very day I am declaring that I will restore double to you.
13 For I will bend Judah as My bow,
I will fill the bow with Ephraim.
And I will stir up your sons, O Zion, against your sons, O Greece;
And I will make you like a warrior's sword.
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I suggest you get your facts straight.