How Do We Know That the New Testament is Scripture?

Before diving too deeply into this topic, I think it's helpful to understand what the criteria are for acceptance into the biblical canon--that volume of books and letters which are considered Scripture for orthodox Christians. Dr. Bill Mounce (author of some of the best Koine Greek textbooks and curricula available today) has a concise article on this website that I commend to you: What criteria were used to determine the canon of Scripture? With that brief historical introduction, let's dive right in.

Most Christians are familiar with 2 Timothy 3:16, which states:

All Scripture is inspired by God and profitable for teaching, for reproof, for correction, for training in righteousness;

But, we have to be careful with this because what Paul is writing about in this verse is most likely the Old Testament. Look at the two verses that come right before it:

You, however, continue in the things you have learned and become convinced of, knowing from whom you have learned them, and that from childhood you have known the sacred writings which are able to give you the wisdom that leads to salvation through faith which is in Christ Jesus.
— 2 Timothy 3:14, 15

Timothy learned the Scriptures from his childhood--before the NT was put together. Based upon the evidences discussed in my workshop, I think it is safe to say that it is not controversial to assert, "The Old Testament is Scripture and therefore is inspired." But why do we consider the New Testament to be Scripture, too?

Jesus Foretells the Growing of the Canon of Scripture

I think we need to start with the words of Jesus Himself, who seems to have foretold what He was going to do (i.e. inspire more Scripture):

“These things I have spoken to you while abiding with you. 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 said to you.
— John 14:25, 26

“When the Helper comes, whom I will 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.
— John 15:26, 27

“I have many more things to say to you, but you cannot bear them now. But when He, the Spirit of truth, comes, He will guide you 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.
— John 16:12, 13

How might the Holy Spirit bring to remembrance all that Christ taught to those of us who were born long after all who heard Jesus firsthand had died? It would seem rather difficult to bring to remembrance that which you never knew in the first place! To whom is Jesus saying that the apostles would testify, only to those whom they met personally? I think this is a strong indication that more Scripture was about to come, and it was going to penned by the hands of (some of) Christ's apostles.

Did the Apostles Know They Were Writing Scripture?

One might argue that the apostles (being somewhat "dense" at times) didn't really grasp that they would eventually be used by God to extend Scripture, but from Scripture I think we can see that they understood that they were indeed doing just that. God's intention for Paul, the late-comer to Apostleship, was made clear right up front when He called to Ananias in a vision and told him to go restore Paul's sight:

But the Lord said to Ananias, "Go! This man is my chosen instrument to carry my name before the Gentiles and their kings and before the people of Israel."
— Acts 9:15

Paul is credited with writing roughly 2/3rds of the New Testament, and had this to say about his own writings:

but just as we have been approved by God to be entrusted with the gospel, so we speak, not as pleasing men, but God who examines our hearts. (1 Thessalonians 2:4) For this reason we also constantly thank God that when you received the word of God which you heard from us, you accepted it not as the word of men, but for what it really is, the word of God, which also performs its work in you who believe.
— 1 Thessalonians 2:13

For you know what commandments we gave you by the authority of the Lord Jesus.
— 1 Thessalonians 4:2

So, he who rejects this is not rejecting man but the God who gives His Holy Spirit to you.
— 1 Thessalonians 4:8

And lest we think that only those commands that Paul gave verbally were the commands of God, i.e. inspired Scripture, Paul tells us explicitly that his written words carried the full weight of his apostolic authority:

So then, brethren, stand firm and hold to the traditions which you were taught, whether by word of mouth or by letter from us.
— 2 Thessalonians 2:15

If anyone thinks he is a prophet or spiritual, let him recognize that the things which I write to you are the Lord’s commandment.
— 1 Corinthians 14:37

Did you know that Paul quoted Luke's gospel? In doing so, Paul placed the gospel of Luke on the same shelf as the Pentateuch:

For the Scripture says, “You shall not muzzle the ox while he is threshing,” [Deuteronomy 25:4] and “The laborer is worthy of his wages.” [Luke 10:7]
— 1 Timothy 5:18

Peter gets in on the act, too, in his second epistle, wherein he states that the commandments of the Lord are spoken by the apostles:

that you should remember the words spoken beforehand by the holy prophets and the commandment of the Lord and Savior spoken by your apostles.
— 2 Peter 3:2

And he very clearly gives all of Paul's writings the same weight and authority as the Old Testament scriptures:

and regard the patience of our Lord as salvation; just as also our beloved brother Paul, according to the wisdom given him, wrote to you, as also in all his letters, speaking in them of these things, in which are some things hard to understand, which the untaught and unstable distort, as they do also the rest of the Scriptures, to their own destruction.
— 2 Peter 3:15, 16

And, bringing up the rear is the John the Elder, who wrote:

The Revelation of Jesus Christ, which God gave Him to show to His bond-servants, the things which must soon take place; and He sent and communicated it by His angel to His bond-servant John, who testified to the word of God and to the testimony of Jesus Christ, even to all that he saw. Blessed is he who reads and those who hear the words of the prophecy, and heed the things which are written in it; for the time is near.
— Revelation 1:1-3

Hearkening back to Peter,

...no prophecy was ever made by an act of human will, but men moved by the Holy Spirit spoke from God.
— 2 Peter 1:21

What About Fulfilled Prophesies?

We don't typically think of the New Testament as being hugely prophetic. At first glance, it seems more doctrinal (the epistles), historical (Acts) or narrative (the Gospels). Of course, there's the book of Revelation which is replete with difficult-to-grasp imagery and non-linear story lines. But, that's not to say that the NT is devoid of predictive prophecies which have already been fulfilled. Without taking too much more time (I'll leave it to you to find the references), I'd like to quickly bring to your remembrance the following prophesies made in the NT which have already been clearly fulfilled (at least in part):

Jesus told Peter that Peter would deny Christ three times;
Jesus said that the temple would be destroyed, and it was...in AD 70 by Titus;
Jesus said the church would survive and grow;
Jesus said the Gospel would be preached in all the world; and
Jesus predicted his own death, and resurrection.

So, all in all, I think we have a pretty solid case for believing that the New Testament is Scripture and as such, is θεόπνευστος (theopneustos)--God-breathed.

Dan KreftMay 8, 2018