When discussing Scripture, Christians are referring to both Old and New Testaments. The apostle Paul declared that the holy Scriptures “are able to make you wise for salvation through faith in Christ Jesus. All Scripture is God-breathed and is useful for teaching, rebuking, correcting and training in righteousness, so that the man of God may be thoroughly equipped for every good work” (2 Timothy 3:15–17). If Scripture is “God-breathed,” then it is not man-breathed, and, although it was penned by men, those “men spoke from God as they were carried along by the Holy Spirit” (2 Peter 1:21). No man-made writing is sufficient to equip us for every good work; only the Word of God can do that. Furthermore, if the Scriptures are sufficient to thoroughly equip us, then nothing more is needed.
Colossians 2 deals with the dangers a church faces when the sufficiency of Scripture is challenged and merged with non-biblical writings, full of ungodly theology and concepts. Paul warned the church at Colosse: “See to it that no one takes you captive through hollow and deceptive philosophy, which depends on human tradition and the basic principles of this world rather than on Christ” (Colossians 2:8). Jude says it even more specifically when he writes, “Although I was very eager to write to you about the salvation we share, I felt I had to write and urge you to contend for the faith that was once for all entrusted to the saints” (Jude 1:3). Notice the phrase “once and for all.” This makes it clear that no other writings, no matter how godly the pastor, theologian, or denominational church they may come from, are to be seen as equal to or completing the Word of God. The Bible is all that is necessary for the believer to understand the character of God, the nature of man, and the doctrines of sin, heaven, hell, and salvation through Jesus Christ. Paul’s words to the Galatians indicate the seriousness of delivering a message outside the Bible: “If we or an angel from heaven should preach a gospel other than the one we preached to you, let him be eternally condemned!” (Galatians 1:8).
Perhaps the strongest verses on the issue of the sufficiency of the Bible come from the book of Psalms. In Psalm 19:7–14, David rejoices in God’s Word, declaring it to be perfect, trustworthy, right, radiant, enlightening, sure and altogether righteous.
The sufficiency of Scripture is under attack today, and, sadly, that attack comes far too often in our own churches. Management techniques, worldly methods of drawing crowds, entertainment, extra-biblical revelations, mysticism, and some forms of psychological counseling all declare that the Bible and its precepts are not adequate for the Christian life. But Jesus said, “My sheep hear my voice and I know them and they follow me” (John 10:27). His voice is all we need to hear and the Scriptures are His voice, completely and utterly sufficient.