‘Seals’ and ‘Marks’ are symbolical Biblical language for an inward spiritual reality, not a literal, visible sign on or under someone’s skin. If that weren’t the case, ‘the mark of the beast’ could be given to someone against their will, and the Bible makes clear that those who receive such will inherit God’s wrath and be sentenced to Hell (Rev 14:9-11). A person’s eternal destiny then would then be determined by another, which contradicts the testimony of the entire Bible. A spiritual seal or mark is given by God to someone based on that person’s freewill choice–God, in His sovereignty, has allowed people to choose life or death (Deut 30:19).
God seals the righteous in the OT:
The LORD said to him, “Go through the midst of the city, even through the midst of Jerusalem, and put a mark (H8420 תו tav) on the foreheads of the men who sigh and groan over all the abominations which are being committed in its midst.” Eze 9:4
God seals the righteous in the NT:
They were told not to hurt the grass of the earth, nor any green thing, nor any tree, but only the men who do not have the seal (G4973 σφραγίς sphragis) of God on their foreheads. Rev 9:4
God marks the unrighteous in the OT:
And the LORD said unto him, Therefore whosoever slayeth Cain, vengeance shall be taken on him sevenfold. And the LORD set a mark (H226 אות ‘owth) upon Cain, lest any finding him should kill him. Gen 4:15
God marks the unrighteous in the NT (By God allowing a person to choose to be marked, he is thus marked by God):
And he causes all, the small and the great, and the rich and the poor, and the free men and the slaves, to be given a mark (G5480 χάραγμα charagma) on their right hand or on their forehead. Rev 13:16
Were these physical or spiritual seals and marks? Certainly we can see the sealing of the righteous is spiritual–wouldn’t it then follow that the unrighteous are likewise spiritually and not physically marked?
Which is emblematic of your life–are you sealed by God, trusting by faith in Jesus Christ and His death on the cross for your sins, or are you turning from God, pursuing your own path, your life marked with sin and self-sufficiency? When the times become even more difficult to choose Christ, when it becomes life or death, who will you side with?