Because they are the wrong color the wrong religion belong to the wrong political parties love people that are not approved of. How is that CHRISTIAN? So are those CHRISTIANS really not at all? Why do they present themselves as being Christian when they are not remotely following the teachings of CHRIST? Liars? Pretenders?
Revelations 7:3-8
Revelations 14:1
Revelations 14:3-5
You can interpret it however you want. After all, nothing in Revelations is literal.
Some interpret those passages to mean that only 144,000 will be admitted to Heaven.
There are other interpretations, of course.
But given the billions of people who have populated the Earth, none of them make sense.