First begotten from the dead, as in Revelation 1:5, signifies truth in act and operation, which is the good of life, and which is the primary of the church. It also signifies the Lord with respect to his humanity because he is divine truth itself united to divine good, from whom all men, who in themselves are dead, but with the Lord are made alive.

(Odkazy: Apocalypse Revealed 17)

345. Having the seal of the living God. This symbolically means, who alone knows the character of each and every person, and can distinguish and separate them from each other.

Since they were sealed on their foreheads with the seal, therefore having the seal of the living God, being said in reference to the Lord, means to know the character of each and every person, and to be able to distinguish and separate the servants of God from those who are not servants of God.