The fact that it is the oldest institution in history and hasn’t gone back on any of its official doctrines in 2000 years despite pressure from kings and having some bad popes is proof that Jesus is keeping his promise about the Holy Spirit protecting the one true church he founded. It is the only church proving continuous Apostolic succession with an unbroken line of popes (successors of Peter, the first bishop of Rome). We were on our 4th pope before the last book of the Bible was finished being written.