In the NT itself you have plenty of other writers beside Paul saying they made careful search and inquiry into the Hebrew scriptures in order to get the answers from the "Spirit of Christ within them". So not witnesses or somebody who knew somebody who knew somebody who knew Jesus:
1 Peter, 1:10-12 Concerning this salvation, the prophets who prophesied of the grace that was to be yours made careful search and inquiry, inquiring about the person or time that the Spirit of Christ within them indicated, when it testified in advance to the sufferings destined for Christ and the subsequent glory. It was revealed to them that they were serving not themselves but you, in regard to the things that have now been announced to you through those who brought you good news by the Holy Spirit sent from heaven - things into which angels long to look!
Indeed that's how most religions begin - some guy claiming to be visited by celestial beings: Mohammed by Gabriel, Joseph Smith by Moroni, Hubbard by alien spirits.
There's a good lecture on it by Richard Carrier on how Christianity began and other religions
https://youtu.be/WUYRoYl7i6U
1 Peter, 1:10-12 Concerning this salvation, the prophets who prophesied of the grace that was to be yours made careful search and inquiry, inquiring about the person or time that the Spirit of Christ within them indicated, when it testified in advance to the sufferings destined for Christ and the subsequent glory. It was revealed to them that they were serving not themselves but you, in regard to the things that have now been announced to you through those who brought you good news by the Holy Spirit sent from heaven - things into which angels long to look!
Indeed that's how most religions begin - some guy claiming to be visited by celestial beings: Mohammed by Gabriel, Joseph Smith by Moroni, Hubbard by alien spirits.
There's a good lecture on it by Richard Carrier on how Christianity began and other religions
https://youtu.be/WUYRoYl7i6U
