The fact that those who take The Mark cannot repent of it later tells us something interesting, for considering the whole counsel of Scripture, this would mean that taking The Mark is synonymous with a conscious, willful rejection of the Lord Jesus.
Hebrews tells us that it is only those who have heard the truth and rejected it who cannot find repentance, the door of grace is closed to them.
So the Mark of the Beast implies a certain degree of Christianization of the whole world and then a rejection of Christ for another christ. For it’s not solely that they worship a man, The Beast, as if he were God, cos people have always done that; Hindus do that, and they also find repentance and get saved out of it, but they are not those who have heard the Gospel and then made a conscious rejection of the Lord Jesus. So for The Mark to be the unforgivable sin, then it is not a sin of ignorance, but of knowledge.
So the real issue with the Mark of the Beast is WHO they are rejecting, more than who they are accepting.
Ian Vincent 
April 21, 2013 at 4:22 am
yes.
April 23, 2013 at 1:23 pm
We know this is right because the bible clearly teaches that the anti-christ’s followers are given over to a strong delusion precisely because they have received not the love of the truth (2 Thessalonians 2:10-12).
It’s the rejection that is the issue: everything flows from that.