I hear most of Israel is made up of atheists. I heard like 90% from multiple people even pastors of different faiths.
You heard wrong. In Israel over 75% of the population practices the religion of Judaism. Atheism is a minority. The original founders of Israel were athesits and agnostics, being holocaust survivors, some of whom become atheists as a result of the holocaust. The reason that many people think that Israel is "atheistic" is that many Jews in Israel identfy themselves as "secular" Jews and because only 2% are Messianic or Chrisitan. But in Israel, "secular" doesn't mean nonreligious like it does here in the US. In Israel, "secular" simply means that you are not an Orthodox Jew. In Israel, secular Jews are religious Jews who are traditionally Jewish, without ascribing to Orthodox Jewish traditions or customs. They are still kosher, still Torah-observant.
Well, of those who are religious jews, they go to an old wall in large groups, they pray the scriptures in front of it rocking back and forth, they make pilgramedges from the four corners of the earth to pray before it, they kneel before it, they kiss it, they take pieces of it home with them.
They pray and rock back and forth. The rocking is called "davening" and they do that because they want their entire body and being to be involved in praising and praying to God. It goes back to loving God with all your heart, soul and strength.
They don't necesarily make pilgrimages specfically to pray at the wall, although they do take to do so. They kiss it, as it is the holiest place in the Jewish religion. It is no different than a soldier overseas who might kiss a photograph of his wfe and children. It is not an act of worship but an act of affection for what the picture represents. The same way with the wall. The wall repsresents someone greater and kissing the wall isn't an act of worship for the wall, but at symbol of one's affection for the Lord and desire to be in His presence.
Isnt Judaism based on the Old Testament.
Not really. Judaism is what become of the Pharisees. The Romans destroyed the temple and sacked Jerusalem. Once the Temple was destroyed, the Jewish religion had to be redefined as a result of the loss of the temple. Judaism as we know it was born in 72 AD at a city named Yavneh under the leadership of Rabbi Yochanan Ben Zachai.
Isnt the Old Testament much more strict than the new?
Are they guilty of Idolatry?
Also, I hear there are steps taken to rebuild the temple, restore the priesthood, and have animal sacrifice. Wouldnt that be a mockery of the redemptive work of Jesus Christ?
like sayin, "Lord you are not the lamb of God slain for us, you're just a criminal and false prophet who died on a cross, so we have to continue slitting the throats of lambs to atone for sins"
They don't think in those terms. They are trying restore the ancient faith lost in 70 AD. Their motives are not to mock Christ, but bring back what they think honors God.