Here is the 144,000, 12k from the 12 tribes, sometimes called the remnant of Israel.
Clearly it is people of Israel.
Re.7:3 Saying, Hurt not the earth, neither the sea, nor the trees, till we have sealed the servants of our God in their foreheads.
4 And I heard the number of them which were sealed: and there were sealed an hundred and forty and four thousand of all the tribes of the children of Israel.
But to follow up is this.
Re 7:9 After this I looked, and behold, a great multitude which no man could number, from every nation, from all tribes and peoples and tongues, standing before the throne and before the Lamb, clothed in white robes, with palm branches in their hands
A Multitude NO MAN Can Number!!!
144,000 plus! But brilliant men can justify their every inconsistancey! (Living Bible)