Why would it not only apply to the 12???
Or did God only choose 12 to follow the Son and no others???
@Tambora
You seemed to be using that passage in a bigger context. I can see know that you may not have meant it that way. I would look at David in the Psalms passage as something like a fleshly prayer. Something like Lord take their physical lives (book of living) so that they can't repent and be saved (book of life). I think it's from a mans perspective. I believe, if I recall correctly, David later repents from that viewpoint.
The book of life. I'm not sure that Judas was ever in it. Interesting question, though. There is a passage in Luke 10:20, I believe when Jesus was addressing the seventy and said something to the effect that their names are written in heaven. Is that book of life? I honestly don't. But that passage could be taken as a general statement. These two passages below in Luke seem to support the idea of perseverance being the evidence of a genuine faith from 1 John 2:19.
1 John 2:19 They went out from us, but they were not of us; for if they had been of us, they would have continued with us; but they went out that they might be made manifest, that none of them were of us.
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Luke 22:21-22 But behold, the hand of My betrayer is with Me on the table. And truly the Son of Man goes as it has been determined, but woe to that man by whom He is betrayed!"
Luke 22: 28-30 But you are those who have continued with Me in My trials. And I bestow upon you a kingdom, just as My Father bestowed one upon Me, that you may eat and drink at My table in My kingdom, and sit on thrones judging the twelve tribes of Israel."
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The significance of the Seal, as God calls our receiving of the Holy Spirit in the NT, is that only that one who made it can break it. Remember, Jesus is the Author, and Finisher of our faith. He could not be the Finisher if we could lose it. And the Seal, God Promise, would be broken by us, which I don't believe can happen. If someone backs away from their faith, permanently, then they only manifested that they never had it. Let me know what you think.
Dave