What is the difference between how the twelve knew Jesus and how Paul knew Jesus?
The twelve knew Jesus in the flesh and during the forty days after His resurrection, but they knew nothing of the ascended Lord. Paul, by contrast, received his revelations directly from the ascended Lord in glory, which the twelve could not comprehend.
Les explains that these same apostles, who once seemed to be somewhat, no longer had the preeminence they enjoyed in the earthly ministry and early Acts. Paul writes by inspiration of the Holy Spirit, and God accepts no man's person, so Peter was no greater than anyone else. They added nothing to Paul because they had no comprehension of the revelations Paul received from the ascended Lord. They knew Jesus in the flesh and during the forty days after His resurrection, but they knew nothing of the ascended Lord; Paul received all from the ascended Lord in glory.