WHO ARE THESE 144,000?
First of all, before taking our word for it read Numbers chapter 1.
Revelation 7:4 The 144,000. God's promise to his chosen people. Even though they are not Christian, they are believers in the Heavenly Father. They are Jewish. Read The Book of Numbers chapter 1.
Why do many cults such as the Jehovah's Witnesses have trouble with this verse? You would really have to be extremely dense to confuse this verse in Revelation 7 with anything else but the people named here. This is one of the most easiest to understand verses in all the Bible.
It clearly states who they are. These are not the promised or the chosen people in any way. These are some of the unsaved who did not believe in Jesus. They are not revered here at all. These 144,000 are still failures in the Lord's eye but they are Jews, His people.
He is reaching out with his heart to grab more of His promised 12 tribes into the millenium. Because in His heart there is not enough of them saved initially through the Rapture. (see Jeremiah 30:10 "I will spare your seeds").
According to Numbers, He most likely will take 12,000 descendants of each of the 12 tribes. They will have a mark on their foreheads (emet) meaning "truth". They may not be tempted nor harmed by satan during the rest of Tribulation. He is specially protecting them here in a secluded place and teaching them. Giving them superior knowledge to teach and witness to others for the very final days.
Revelation 14:1-5
"I looked and there was the Lamb standing upon Mt. Zion and with Him 144,000 having His name and His Father's name upon there foreheads."
Here they are ready to witness and teach to all who are left. Now they are the Lord's chosen again.