Why do Protestants trust what Paul and Luke wrote 100%? This has always been a big question for me.

I can understand that many Christians believe there is good evidence for the resurrection of Jesus, and that gives a basis for their faith in the teaching of Jesus and the gospels that speak about him and his disciples.

But the same Christians do not believe, for example, Mohammad's claims. One big reason is that Mohammad basically claimed a personal revelation that only he received. There could be any number of reasons for that, including epileptic episodes etc.

Now Paul by his own account had a personal experience on the road to Damascus, and it kind of resembles Mohammad's experiences. So that by itself wouldn't be enough to have a leap of faith and say that whatever Paul wrote is therefore true.

Having been investigating this matter for quite some time, all the evidence that I see points away from the conclusion that Paul and the author of Luke/Acts are trustworthy. However, if I list all this evidence, the question will get too long. As a result, I will write an answer as StackExchange encourages, and include the evidence there. However, due to the nature of the question and the unsatisfactory (to those who believe Paul implicitly) answer, I will probably get downvoted on both the question and the answer. Hopefully not, since this is a serious matter.

The reason it is serious - especially to Jewish Christians - is because:


God said that many Laws are forever (examples)
Jesus taught in the Sermon on the Mount that any Jews who set aside even the smallest commandment and teach others to do so, will be called least in the Kingdom of Heaven (Matthew 5:19)
Rather than saying the Law was powerless to save, Jesus said, "if you want to enter into life, keep the commandments" (see Matthew 19:16–22). And in fact even as Jesus taught about the Son of Man being betrayed to the Gentiles, and will rise on the third day, he didn't say that the Law would be nailed to the cross.


This makes it crucial to ascertain if Paul and Luke are trustworthy, because if they are not, then it's dangerous for a Jewish Christian to stop following the Law, just because Paul said so.

To summarize the question: if you draw a graph starting with Jesus, and to his disciples and their disciples, you get Paul and Luke as basically "disconnected" from the graph. Paul claims he got the revelation from his own visions. Luke describes miracles Paul did. Luke endorses Paul. Paul endorses himself. Paul says he won the argument with Peter. There is no account from the disciples Jesus set up, about any of those things. Why do Protestants just assume Paul is right, and his theology is right, and Luke is trustworthy?

Just to prevent simple knee-jerk potential answers to this question:


Paul is trustworthy because Acts describes him doing miracles. The issue here is that Acts is attributed to Luke, a student of Paul. This man also never met Jesus in real life.
Luke is trustworthy because his details were verified. Being able to correctly name people and places around you doesn't automatically mean the miracle claims are true, how do we know this wasn't just propaganda to boost Paul among the Gentile churches?
2 Peter 3:16 endorses Paul. Yes as far as I know this is in fact the ONLY place outside Paul + Luke that Paul is even mentioned by name. However there is a huge problem. Most modern New Testament scholars don't believe 2 Peter was written by Peter. So if your only evidence for Paul's authority outside their own writings is 2 Peter, then that means you are disagreeing with most New Testament scholars. Also, the original Church acceptance was also quite contentious.


In short, do Protestants have any logical reasons to believe in the authority of Paul and Luke? These reasons have to be better than the reasons they reject in other cases, such as Mohammad, Joseph Smith, etc. I can understand that you can just choose to believe on faith, but I am looking for solid logical arguments.
Protestants trust what Paul and Luke wrote for the same reason Catholics, and all other Christians, believe what they wrote is correct: because the rest of the New Testament testifies to the veracity of what they say.

Peter asserts Paul's writings are scripture in 2 Peter 3:14-16. The first several chapters of Acts are about everyone but Paul. And, from Paul's conversion to his ministry is a period of several years, wherein the other Apostles are followed and written about.

In Acts 15, where the Council at Jerusalem is recorded, several Apostles affirm Paul's work.