Question:
Who are the 24 elders mentioned in Revelation 4:10?

Answer:
All the heavenly company, the Old and New Testament saints, for “Jesus said unto them, Verily I say unto you, That ye which have followed me, in the regeneration when the Son of man shall sit in the throne of His glory, ye also shall sit upon twelve thrones, judging the twelve tribes of Israel” (Matthew 19:28). See also: Revelation 5:8-10.
All the saints will be clothed in fine linen— “Let us be glad and rejoice, and give honor to Him: for the marriage of the Lamb is come, and His wife [the church] hath made herself ready. And to her was granted that she should be arrayed in fine linen, clean and white: for the fine linen is the righteousness of saints. . . . And the armies [the Old and New Testament saints] which were in heaven followed Him upon white horses, clothed in fine linen, white and clean” (Revelation 19:8, 14).The church is “a kingdom of priests” to God (Revelation 5:10). “But ye are a chosen generation, a royal priesthood, an holy nation, a peculiar people; that ye should show forth the praises of him who hath called you out of darkness into his marvellous light” (1 Peter 2:9).