Whoever listens to you listens to me. Whoever rejects you rejects me. And whoever rejects me rejects the one who sent me. Luke 10:16, NABRE
I came across this passage again in my regular reading today and it motivated this blog post. The important things to notice here are (first) that the authority of the seventy[-two] to preach and to heal was explicitly given to them by Jesus. They do not act on their own volition or initiative; rather they act on the authority of Christ. And the second thing to notice is how Christ confirms the authority He gives them: to hear them is to hear Him; to reject them is to reject Him.
We have here another reason for firmly holding that the Lord Jesus Christ founded a visible Church. Why? Because apart from a visible Church to whom authority is given by Christ, it is impossible to know who (among the many who claim it) speaks with His authority and who does not. We would be left with a blind judgment call. But it is evident that this is not what Christ intends for His people, since He makes clear both the fact that these seventy[-two] are sent to represent Him, and the fact that He considers one’s reception of them the same as his reception of Jesus Himself. “He who hears you hears Me.” This is what He says.
Apostolic succession matters. The visible Church matters. Apart from these institutions we are simply not able to distinguish those who only claim to speak for Jesus from those who actually have His authority. The alternative to the visible Church and apostolic succession is chaos concerning the message of the Gospel. If Christ founded no visible Church or if (per impossibile) that Church vanished somehow, then we can have no assurance about the content of the Gospel. It is not enough to be able to appeal to the text of the Scriptures; anyone can do that, and the bare appeal to God’s Word does not imply that one has authority from God to speak on His behalf. That is why we need a visible Church whose authority is vouchsafed by being passed on from one generation to the next. That is why Matthias was chosen to replace Judas Iscariot (Acts 1:20-26). If it was understood that apostolic authority was to die with the apostles then eventually there would have been fewer than twelve apostles anyway (and eventually none at all). Hence it would have been superfluous to have replaced Judas if his office was not intended to be perpetuated. Likewise, it cannot be that the number twelve was itself the critical thing since Jesus Himself appointed St. Paul as a thirteenth member of the college.
It remains then that it was not mere numbers which mattered but rather perpetuation of authority; and this is why Christ founded, and we need, a visible Church. Christ’s Church speaks for Him and so we must listen to her.
Aquinas, Etc. 
I’m reading a book right now that is critical of evangelicals becoming Catholics and Greek Orthodox, and it refers to a point that John Meyendorff made in a 1962 book, The Orthodox Church: Its Past and Its Role in the World Today. On page 233, Meyendorff says: “The College of the Twelve ceased to exist: Herod caused ‘James, the brother of John, to be beheaded’ (Acts xii:2), and no one thought of replacing him by electing a successor in order to keep up the symbolical number of Twelve, as they had in the case of Judas.” What are your thoughts about this? Why was Judas replaced, whereas James was not? Or is there an ancient tradition that says that James was replaced?
Hi James,
According to this page his successor was Simeon. This is repeated (with additional facts about Simeon) here. Obviously this is not recorded in the Bible, so it is an historical tradition. I am not familiar with the sources to be able to say anything about the reliability of the tradition, but I know of no ipso facto reason to doubt it either.
I hope this helps. I do not know why Meyendorff would suggest that St. James had no successor. My thoughts about the matter: the Bible’s silence is nothing more than silence; the only one whose successor is explicitly named in the Bible is Judas’s. The number twelve does not seem to me to be fundamentally important (else the Lord would not have made St. Paul the thirteenth apostle). So what seems to me to be more relevant is the office rather than the number.
Peace,
Fred