This is where the warning given by the Lord God applies: to discern the truth of God's word, one must not place ultimate trust in any human being.
I would like to emphasize that this applies only to God and His word. When it comes to knowing the truth of God and understanding His word, no human being should be trusted as the ultimate authority.
JEREMIAH 17:5
5 Thus saith the Lord; Cursed be the man that trusteth in man, and maketh flesh his arm, and whose heart departeth from the Lord.
Even a person's own understanding of the Holy Scriptures is forbidden by the Lord to be relied upon.
PROVERBS 3:5
5 Trust in the Lord with all thine heart; and lean not unto thine own understanding.
How can the truth regarding our question to God be revealed—namely, what was Judas's sin, and whether he was saved or not? To whom should we ask this question? The Lord has already given us the answer. We should ask Him alone, so that He Himself may reveal the truth contained in His word.
Rather than relying on other people or on our own understanding, we must seek the answer from God, for He alone can reveal the true meaning of His word.
JAMES 1:5-8
5 If any of you lack wisdom, let him ask of God, that giveth to all men liberally, and upbraideth not; and it shall be given him.
6 But let him ask in faith, nothing wavering. For he that wavereth is like a wave of the sea driven with the wind and tossed.
7 For let not that man think that he shall receive any thing of the Lord.
8 A double minded man is unstable in all his ways.
If we let the Lord Jesus Himself disclose the true sin of Judas, this is what He said.
MATTHEW 26:20-25
20 Now when the even was come, he sat down with the twelve.
21 And as they did eat, he said, Verily I say unto you, that one of you shall betray me.
22 And they were exceeding sorrowful, and began every one of them to say unto him, Lord, is it I?
23 And he answered and said, He that dippeth his hand with me in the dish, the same shall betray me.
24 The Son of man goeth as it is written of him: but woe unto that man by whom the Son of man is betrayed! it had been good for that man if he had not been born.
25 Then Judas, which betrayed him, answered and said, Master, is it I? He said unto him, Thou hast said.
If we read and understand what the Lord Jesus said, it is actually very simple. What do you think He intended to convey by His statement?
Especially what is stated in verse 23.
23 And he answered and said, He that dippeth his hand with me in the dish, the same shall betray me.
Those whom the Lord Jesus chose understood this, because they believed that the Lord often spoke in parables. That is why they continually asked Him questions.
MARK 4:34
34 But without a parable spake he not unto them: and when they were alone, he expounded all things to his disciples.
MARK 13:10
10 And the disciples came, and said unto him, Why speakest thou unto them in parables?