Rom 11:25 For I do not desire, brethren, that you should be ignorant of this mystery, lest you should be wise in your own opinion, that blindness in part has happened to Israel until the fullness of the Gentiles has come in.
Because the Jews rejected our Lord Jesus Christ, Yahweh gave them a spirit of stupor concerning spiritual things and they will be blind until Rapture. However, God has reserved the elects, who will be saved by grace.
Rom 11:5-7 Even so then, at this present time there is a remnant according to the election of grace. And if by grace, then it is no longer of works; otherwise grace is no longer grace. But if it is of works, it is no longer grace; otherwise work is no longer work. What then? Israel has not obtained what it seeks; but the elect have obtained it, and the rest were blinded.
The elect Jews keep the laws and words of Moses to the latest and are not hypocrites who are blind. They will search scriptures to ensure that it is in God's words or will.
Mat 23:1-3 Then Jesus spoke to the multitudes and to His disciples, saying: "The scribes and the Pharisees sit in Moses' seat. Therefore whatever they tell you to observe, that observe and do, but do not do according to their works; for they say, and do not do."
Temple builds on Temple Mount?
The Temple Institute, Rabbis and Jewish leaders are all ready to build the Temple of God on the Temple Mount, which they believed is Mount Moriah or Mount Zion. They just accepted what was wrongly handed down to them (without checking the facts or truth) by traditions. Similarly, Christians today accept all types of wrong teachings (mainly heresies) as truth without verifying with the words of God.
But the elect Jews spent time searching scriptures to ensure that they are following truth.
What we call the Temple Mount, with 36 acres of land was actually Fort Antonia housing a legend of 6,000 Roman soldiers during the days of our Lord. Across the Kidron valley was the city of David where the temple of God was built on Mount Zion. In 691 AD, the Muslims built the Dome on the Rock on Fort Antonia and named it Haram al-Sharif (the Noble Sanctuary) followed by Al-Aqsa Mosque in 705 AD.
[ Where Will the Next Temple of Jerusalem Be Built?]
All these years while the Dome on the Rock and Al-Aqsa Mosque was on Haram al-Sharif, the Temple of God lies in ruin on Mount Zion. It was only in the 17th Century that Haram al-Sharif was called the Temple Mount by the Jews.
[ The True Site of the Holy Temple in Jerusalem ]
[ The Coming Temple - Full Documentary ]
What if Temple Mount is not the true site for Temple of God?
So when these elect Jews (the remnants) see that the Temple is built on the Temple Mount (the wrong site), then they know that this Temple is not God's Temple but the devil's. They will reject this temple and the Antichrist and will not serve nor worship him. So at Rapture, they will believe our Lord Jesus, the One whom they pierced.
Rom 11:23 And they also, if they do not continue in unbelief, will be grafted in, for God is able to graft them in again.
Rom 9:27 Isaiah also cries out concerning Israel: "Though the number of the children of Israel be as the sand of the sea, The remnant will be saved."
Though the population of the Jews worldwide is about 14.5 million, yet only a remnant of 144,000 Jews (1%) will be saved at Rapture.