Scripture says about Judas:
John 17:12. While I was with them in the world, I kept them in thy name: those that thou gavest me I have kept, and none of them is lost, but the son of perdition; that the scripture might be fulfilled.
Mark 14:21. The Son of man indeed goeth, as it is written of him: but woe to that man by whom the Son of man is betrayed! good were it for that man if he had never been born.
Also:
Jesus answered them, Did not I choose you the twelve, and
one of you is a devil? Now he spake of Judas the son of Simon Iscariot, for he it was that should betray him, being one of the twelve. Jn 6:70,71
But Judas Iscariot, one of his disciples, that should betray him, saith, Why was not this ointment sold for three hundred shillings, and given to the poor? Now this he said, not because he cared for the poor; but because
he was a thief, and having the bag took away what was put therein. Jn 12:4-6
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I place the regret of Judas in the same catagory as 'the weeping and gnashing of teeth' of those that have been cast out into the outer darkness.
Consider Essau's regret:
lest there be any fornication, or profane person, as Esau, who
for one mess of meat sold his own birthright. For ye know that even when he afterward desired to inherit the blessing, he was rejected; for he found no place for a change of mind in his father, though he sought it diligently with tears. Heb 12:16,17
Consider the regret of Israel when they were rejected from entering into the promised land:
35 Surely there shall not one of these men of
this evil generation see the good land, which I sware to give unto your fathers,
45 And ye returned and wept before Jehovah; but Jehovah hearkened not to your voice, nor gave ear unto you. Dt 1
When the door is shut from on high................it's all over with but the crying.