Biblical explanation
Revelation 7 says: "I heard the number of them which were sealed: and there were sealed an hundred and forty and four thousand." Revelation 7:4, KJV They are associated with the tribes of Israel in a highly structured symbolic list. Revelation 14 describes them standing with the Lamb on Mount Zion, having the Father's name written on their foreheads. They: Follow the Lamb. Have been redeemed. Are described as firstfruits. Have no lie in their mouths. Are described as blameless. Revelation 14:4-5. The Bible explicitly gives the number 144,000. The major interpretive question is whether the number is literal, symbolic, or both in some sense. Revelation frequently uses symbolic numbers, but it also gives concrete numbers. Therefore, Scripture should be allowed to define the characteristics of the group rather than forcing the number into a preconceived theory. What is unmistakable is their allegiance to the Lamb.
Key takeaway
The great controversy reveals God's character as Christ ministers as our High Priest in the heavenly sanctuary. The dead await the resurrection, Christ's return will be visible and personal, and prophecy calls believers to faithful mission rather than date-setting or fear.