Is the 144,000 in Revelation 7 a literal number of saved individuals at the end of time, perhaps a subgroup of the great multitude in 7:9? To take the number literally requires several assumptions. It assumes that the twelve tribes of Israel still exist in a meaningful way. It assumes that most things in Revelation should be taken as literal unless proven otherwise. It often assumes that this is a reference to Jews who come to Jesus in the final crisis of the world’s history, although some people suggest that the numbers are literal but the tribes are symbolic in some way, a distinction the text itself does not make.
I believe that a symbolic reading of the number is to be preferred for a number of reasons. First of all, the list of twelve tribes is not found in this form anywhere else in the Bible or historical experience, it is not a literal or normal list. For example, Judah is listed first, instead of Reuben. Reuben was the actual first-born of Jacob, but Judah became the leader of the family later on. Joseph (father of Ephraim and Manasseh) is listed among the twelve, but so is Manasseh, his son. To make things stranger, Joseph’s other son, Ephraim, is missing from the list. The tribe of Dan is also missing from the list while Levi, the thirteenth tribe in the Israelite national census (compare Num. 1:5-15; 13:4-15) is included. They are also not listed in birth order (Gen. 49:3-28). So a symbolic reading of the tribes is clearly indicated, which would imply that the number is also symbolic.
Second, Revelation 1:1 indicates, right at the start of Revelation, that the whole book of Revelation was “signified” (KJV, Greek: esêmanen, often translated “made known”). The Greek word for “signified” represents symbolic language that refers to the future. See the comments on Revelation 1:1 in my Facebook commentary on Revelation. So Revelation is different from the rest of the Bible. Generally, you take the Bible at face value unless it is obvious that a symbol is intended. In Revelation you are expected to do the opposite. The best way to approach the text of Revelation is to treat everything as a symbol, unless it is obvious that a literal meaning is intended. This applies also to the number in Revelation 7:4-8. A parallel to the 144,000 is the 200,000,000 of Revelation 9:16. A literal army that size is hard to imagine, even in today’s world.
Third, reading the tribes as literal descendants of Jacob flies in the face of the fact that at least ten of those tribes are essentially lost to history. The so-called “ten lost tribes” were taken captive by the Assyrians around 722 B.C. and scattered throughout the Assyrian Empire, being replaced by people from at least five other nations (1 Kings 17). By the time of the return from Babylon (539 B.C.) the identities of the ten tribes was already largely lost. While some Jews today can still trace their lineage back to Judah, Benjamin or Levi, most western Jews today trace their lineage back to European converts in the Middle Ages. The twelve tribes of Israel are largely lost to history today. For these reasons a symbolic reading or Revelation is to be preferred.