Marketing and organizing ability. The Catholic Church is the oldest continually existing organization in the world. I think it was Peter and Paul who were the geniuses behind the establishment of this organization, but I’m not sure. It was some of the early leaders who built a structure with a stable means of power transfer that was protected from governments that competed for land.
The Church was very clever in insulating itself, fairly successfully, from efforts by national governments to coopt it. I think it did this by allowing itself to be somewhat coopted at times. They knew how to make practical alliances and agreements to keep the organization together. For part of the time, they even had a working military force.
Somehow they were able to maintain their status as a quasi-state that could exist simultaneously with any other state (except those that expelled Catholics). They also had a long term perspective that allowed them to wait out many of their enemies. The Church survives while all other governmental organizations fail sooner or later.
I believe this was all set in place in the early years. Hence Peter and Paul. Maybe Peter was the big time organizer. In any case, he must have known something about organizations because he built one that has lasted longer than any other. It is remarkably stable. It has had its schisms and wars, but it has held together throughout all of that.
What keeps an organization together is partly the bureaucracy and power structure, but I think what is most important is the idea. It is the idea that must attract people and bind them to the organization and the defense of the organization and the growth of the organization.
It probably didn’t even matter what Jesus really did or who he really was. He was a good scaffolding on which to place this idea; this myth; that allowed Peter to bind people together around the world. Without Peter (or whoever), Jesus would have just been another prophet in the desert. Peter was responsible for creating the myth and creating the organization. He was one of the world’s greatest geniuses in that way.