Palestinians don't believe in the same god. Jews stated that Israel is a religion based country and that long ago Abraham promised the land to the Jews, but Muslims and Jews don't believe in the same god. Therefore, that does not apply to them and they should get their share of the land.
Palestinians stayed in Israel. They never left. The Jews left to go live somewhere else, then the Jews came back and made Palestinians leave their homes and everything in it. There is no mark or point in history that the Palestinians didn't live in Israel.