Alongside the fact that we need Scripture in order to be saved and know God’s will for us is the fact that Scripture is all we need in order to know the good news of Jesus and in order to know God’s will for our lives. Scripture is necessary, and it is also sufficient. The Bible “contains all the words of God we need for salvation, for trusting him perfectly, and for obeying him perfectly” (Grudem, Systematic Theology, 127).
Properly understood, this can be a shocking statement for some people. Even if we grant that the Bible is necessary, can we really claim that a book which is thousands of years old is all we need? Can it really be true that these ancient words provide everything we need – without any “improvement” or addition at all?
Yes, it is absolutely true. And the reason it is true is because these are the very words of God. The one God who knows all things – and has always known all things – has told us what we need to know. This does not mean He has told us everything we might like to know (Deut. 29:29), but it does mean He has told us everything we need to know.
This truth is seen most clearly in 2 Tim. 3:15-16. Paul tells Timothy to continue in what he has learned. He reminds Timothy of “the sacred writings, [i.e. God’s Word] which are able to make you wise for salvation through faith in Christ Jesus.” Notice the striking immensity of Paul’s statement: the sacred writings are able – on their own, without anything else – to make a person wise for salvation. Without a doubt, God must work in a person’s heart and give His Holy Spirit, but the only “knowledge” and “material” needed is God’s Word. That Word is sufficient to bring salvation. In fact, this is precisely what has happened in your life if you are a Christian. James says that God “brought us forth by the word of truth” (James 1:18). Peter reminds us that we have been born of “imperishable seed…through the living and abiding word of God” (1 Pet. 1:23). The Scriptures are sufficient to give life.
Even more, the Scriptures are sufficient to guide and direct us in the will of God. Paul goes on to tell Timothy that the Scriptures – breathed out by God – are “profitable for teaching, for reproof, for correction, and for training in righteousness, that the man of God may be competent, equipped for every good work” (2 Tim. 3:16-17). Again, notice the immensity of Paul’s words: the Scriptures are able to equip the man of God for every good work. Is there something God wants you to do? Scripture is sufficient to tell you that. Is there something God wants you to avoid? Scripture is sufficient to tell you that. The Bible is sufficient not only to give life but to guide life.
But why do we care? Is it really that important that we believe in the full sufficiency of the Bible? Yes. First, it means that we have everything we need to know God, be saved, and live according to His will. We don’t have to go searching somewhere else or read thousands of books or travel thousands of miles to find answers. We can find everything we need in His Word. Second, this protects us from the oppression of other people. Ultimately, God has made clear what He requires and what He forbids. We don’t need the opinions of others in this regard, because we have God’s Word. Put simply: nothing is sin unless it is forbidden by God’s Word either explicitly or by implication. And nothing is required of us except what is commanded in God’s Word either explicitly or by implication. Third, this comforts us by reminding us that if the Bible does not speak to something, then it is not essential for our salvation and spiritual life to know that thing. We can rest and be content with what God has said – even if it is not all that we wish He would have said – because we know that what He has said is enough.
So take up the Bible and read it. Read it with confidence that it is God’s Word, and that it will provide everything you need for salvation and for godliness.