Question 2: Why is the Apostles’ teaching important?
The apostles’ teaching is important not only because there are no apostles alive any longer, but because their teaching is the foundation of the Church. Paul, in Ephesians 2:20, makes this point saying the Church is “built on the foundation of the apostles and prophets, with Christ Jesus Himself being the cornerstone.”
Let me explain this by using Jesus’ words in John 14, 15, 16, and 17.
In John 14:26 Jesus said to His apostles, “But the Helper, the Holy Spirit, whom the Father will send in My name, He will teach you all things and bring to your remembrance all that I have said to you.”
Later He said this to them in John 15:26-27, “When the Helper comes, whom I send to you from the Father, that is the Spirit of truth who proceeds from the Father, He will testify about Me, and you will testify also, because you have been with Me from the beginning.”
In John 16:13 Jesus told them, “But when He, the Spirit of truth, comes, He will guide you (apostles) into all the truth; for He will not speak on His own initiative, but whatever He hears, He will speak; and He will disclose to you what is to come.”
Lastly, in John 17:20-21 Jesus prayed saying this, “I do not ask on behalf of these alone, but for those also who believe in Me through their (the apostles, including Paul, the last apostle) word; that they may all be one; even as You, Father, are in Me and I in You, that they also may be in Us, so that the world may believe that You sent Me.”
So, to review: the Holy Spirit will be sent to the apostles, from the Father, in the name of Jesus. Next, the Holy Spirit will bear witness to, testify, and cause the apostles to remember the Words of Jesus. The Holy Spirit will lead the apostles into all truth and declare to them the things that are to come. Then as a result of the testimony of the Holy Spirit, the apostles will testify and proclaim about Jesus (this is what we see in the book of Acts). Jesus then, prays for us, asking specifically that through the word of the apostles we who believe may be one, as the Father and Jesus are one so that the world would believe Jesus came from the Father.
Did you follow that?
We learn from this that the Spirit who is going to inspire the apostles with truth, specifically “all truth” only speaks what He hears from Jesus and from the Father. So, in turn when the apostles go out to preach, teach, and write letters to all the churches, those words are God’s Words, because they are being inspired by the Spirit, and Spirit only speaks what He hears.
Thus, the apostles preaching and writing should not be thought of as their own, but rather as God’s Words through the power of the God’s Spirit about God’s Son.
This is why the apostles words have power, and why when compiled together they form the New Testament Canon. Their Words, have the same authority as the Words of Jesus, because their Words are God’s Words, given to them through the power of the Spirit.
Christians today have believed through the Words of the apostles, spoken and written. And since we cannot hear them audibly any longer, we read their words. This is the New Testament canon, which is the authoritative word to the Church today. This brings to light the correct interpretation of Matthew 16:18 doesn’t it? “I also say to you that you are Peter, and upon this rock I will build My church; and the gates of Hades will not overpower it.” Is Peter the rock? No. The Rock Jesus is referring to are the Words (Scripture) that will come from Peter and the rest of the apostles. That is the foundation of the Church.
See the progression here: Apostolic representatives who then by the power of the Holy Spirit turn into Apostolic preachers, who then through the inspiration of the Spirit turn into Apostolic writers, who have left in their writings an Apostolic witness for the Church for all time.
Therefore the Bible you hold in your hand is the only Apostolic authority for us today. Or as R.C. Sproul says: “The church is Apostolic in that the teaching of the apostles as contained in the sacred Scripture is the foundation of the Church and the authority by which the Church is governed.”