Where is it written in the Bible?

When I studied in Haidar Tashbar at the house of Maran the Chazon Ish, I was amazed.
The Rabbis said that the prophet said that the state would last 40 to 50 years at most, and they felt at the height that they had a prophecy and knew what would happen.
The years have passed and today, God willing, my children are being educated in religious Zionism.
But I'm still curious where it is written in the Zhva?
Asking the Rabbis is not appropriate, most of them have already been covered with earth.
Maybe the rabbi knows where it is written in the Chazva?
They would say that with complete confidence.

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