Some say the 144,000 in the book of Revelation are the great crowd, I.e., the two groups are the same. This is a view oftentimes pushed by Amillenialists.
The following are some reasons why this interpretation just does not fit the vision given to John.
First, it is argued that there is a “hearing-seeing” pattern in Revelation. So that when John hears something then he sees the same thing. But Rev 7 begins with seeing not hearing.
7:1 After this I saw four angels standing at the four corners of the earth, 7:2 Then I saw another angel ascending from the east,
The point is can’t just start in the middle and choose to hear first. Furthermore, in Rev 14 John sees the 144k he heard about in Rev 7 anyway, once again showing that the so-called “hearing-seeing” pattern does not work.
Second, John never calls the Church “Israel” or divides them as “the 12 tribes,” made up of 12k people. The Wycliffe Exegetical Commentary adds:
No clear-cut example of the church being called “Israel” exists in the NT or in ancient church writings until A.D. 160…..This fact is crippling to any attempt to identify Israel as the church in Rev. 7:4. Such an attempt becomes even more ridiculous because it necessitates typological interpretation that divides the church into twelve tribes to coincide with the listing of Rev. 7:5-8, even with all the irregularities in that list. This step is even more anomalous in light of the irregularities in the listing adopted in vv. 5-8. The approach is so misconceived that it does serious violence to the context. It cannot be exegetically sustained. The term Israel must be referred to the physical descendants of Abraham, Isaac, and Jacob. This is the natural understanding and the word’s normal usage in the NT as well as the OT.
Third, it is argued that 144k, 12 tribes, 12,000 are simply representing perfected Christians. But, the 144k, 12 tribes are counted and John says the “great multitude no one could count”! And if all numbers in Revelation are symbols or figures of speech, no number in the book should be taken literally.
Fourth, the 144k are from the 12 tribes of Israel whereas the great crowd is from “every nation, from all tribes and peoples and languages“! Therefore, they cannot be the same group. [NOTE how the innumerable multitude echoes the promise made by God back in Genesis that.] Abraham would be the father of many nations, i.e., “as the dust of the earth,” “as the stars of the sky,” or “as the sand of the sea” (Gen 13:16; 15:5; 16:10; “I will so greatly multiply your descendants that they cannot be numbered for multitude” 22:17-18). In other words, countless is the opposite of counted!
Fifth, the fact that some tribes are left out and others added doesn’t make them somehow Gentiles. The Wycliffe Commentary again notes:
“In about 18 lists of the sons of Jacob or Israel in the OT, different tribes are omitted at different times….the absence of Simeon and Issachar from Deuteronomy 33, of Simeon and Judah from Judges 5, and of Gad and Asher from 1 Chronicles.”
Lastly, John says “after these things I looked” meaning a different group from the previously mentioned group. John is not continuing a description of one and the same group.