The Bible does not provide internal proof for the authorship of the Books of Moses nor the four Gospels nor several of the Epistles. It does not even "authenticate" what its own books are.
The Bible does not define itself: it does not have a "ship manifest" to tell you what's on board, what's part of the cargo and what is not. It doesn't have its own Table of Contents. It did not drop down from Heaven as a set of handsome matched scrolls, and it did not put itself together in leather binding with an index tab for each book. It could not, since so many Bibles have different books.
Somebody put the Bible(s) together. Some assembly was needed.
In order to do that, the person (or body or community) that did that, would have to have authority; because otherwise you have a supposedly authoritative book with no fully authoritative content: impossible.
Either Yohanan ben Zakkai and his circle had the authority, or the 70 scholars of the Septuagint had the authority; or Beth Shammai, or Beth Hillel; or the Masoretes had the authority (6th-10th century AD --- and they were the first ones to devise a Hebrew text with vowels!); or the early Church in its practice and its councils had the authority; or the Syriac, or Armenian, or Georgian, or Egyptian Coptic and Ethiopian Churches had the authority; or a committee of 17th century British royalists in London; or maybe the Latter Day Saints in Salt Lake City; maybe they had the authority --- or not.
You've heard this before.
Where in the above list would you put your checkmark? Or do you have a different authority? Your own?
In what sense can the Bible be said to be self-authenticating?
I’m walking out of the door and won’t be back home until sometime late tonight, so I really don’t have time to give a full thoughtful answer. But I’ll say this much, it’s not a book that can be read and understood by men. Of course the can read and understand words, but the real truths are spiritual in nature. They can only be understood by those to whom they are revealed by the Lord. When the Lord opens your eyes to the truth there can be no doubt as to Divine Authorship. Things that seem foolish or perplexing to most become precious to one who has experienced the miracle of the new birth.
Christ speaking from John 6
44 No man can come to me, except the Father which hath sent me draw him: and I will raise him up at the last day.
45 It is written in the prophets, And they shall be all taught of God. Every man therefore that hath heard, and hath learned of the Father, cometh unto me.
Referencing Isaiah 54, that section of John tells us all those who are saved have been “taught of God.” That doesn’t mean they are taught about God, but they are specifically taught BY God. It’s God who opens eyes to see and ears to hear. And every single person taught by By God will come to Christ and be saved. I believe part of being taught by God is the ability to read the Scriptures with spiritual eyes. A friend of mine likes to say, “if you get it, you got it.” He’s exactly right. Now that doesn’t mean we understand everything. God doesn’t work that way.
Later in John 10, some of the Jews ask Jesus if he is the Christ.
25 Jesus answered them, I told you, and ye believed not: the works that I do in my Father’s name, they bear witness of me.
26 But ye believe not, because ye are not of my sheep, as I said unto you.
27 My sheep hear my voice, and I know them, and they follow me:
28 And I give unto them eternal life; and they shall never perish, neither shall any man pluck them out of my hand.
29 My Father, which gave them me, is greater than all; and no man is able to pluck them out of my Father’s hand.
They didn’t believe because they weren’t among the sheep given to Him by the Father. But His sheep hear His voice. Well, His voice is on every single page of the Bible. I was saved 40 years ago, graduated from a Christian university where I studied a lot of Bible, I have studied it constantly throughout my adult life, yet I have just barely scratched the surface. New truths leap off the page all the time. Books written by men don’t have that power.
Because of our fall in Adam, we are, one and all, spiritually dead from the moment of conception. A fruit tree bears fruit after its kind. It can’t do anything else. We sprung from Adam’s loins, ergo when Adam died, we died. A dead man can’t see or perceive spiritual things unless he has been given new life, which is the gracious gift of God. That’s what happens when a man is born again. At that point we are no longer in Adam, but in Christ, which means he has been by reborn by a miracle of the Holy Spirit.
Now contrary to popular opinion, a man can’t simply decide he will be born again any more than he decided to be born the first time. The early verses of John 3 make that clear. When asked how a man can be born again, Christ likened the work of the Spirit to the wind and said that no one knows where it comes from and it blows where it wishes.
So the New Birth is is a miracle performed in the heart by the Lord. And when that happens, everything changes. A man who has been reborn begins to hate things he once loved, love things he once hated. And he begins to be able to perceive and understand spiritual things in a way that up until that point would have been impossible. For the person to whom this has happened, the Bible becomes self-authenticating. There’s simply no doubt as to its otherworldly origin. As the Bible tells us, it was written by the hands of men as they were directed by the Holy Spirit.
Ok, that’s a rambling answer and, while I could say much more, maybe something in there is helpful for you. I really do have to leave.