What does the Bible mean by the mark of the beast?

The mark of the beast, as mentioned in Revelation 14, is a metaphor for those who have rejected the true gospel and aligned themselves with false ideologies and doctrines. This mark represents the commitment to humanism, relativism, and pluralism, which all divert from the truth of Christ. Those who bear this mark are marked by unbelief, trusting in their works or other beliefs rather than the righteousness that comes through faith in Jesus alone. This severe warning signifies the ultimate judgment that awaits those who remain in such rebellion against God's truth.