Preaching derives its authority from the text of Scripture. Our work of correcting, rebuking and encouraging all flow from a more fundamental command: “Preach the Word” (2 Tim. 2:4). Without the authority of the biblical text there would be no authority for preaching.
There are some who prefer to point past the text and locate the preacher’s authority in the ideas of Scripture, generally in the gospel or more particularly in the person of Christ. In his book Homiletic, for example, David Buttrick writes: “Of course, when we claim that the Bible is our ‘authority,’ we are pointing past text, and past even the gospel in scripture, to God-for-us in Jesus Christ.” Buttrick admits that there are many who believe that God has conferred authority on the Scriptures themselves and are convinced that “the Bible has been designated ‘Word of God’ by divine fiat to rule the church.” But he clearly sees this as a problem.
Buttrick is right to say that the Scriptures point beyond themselves to Christ. Jesus asserted as much when he told the religious leaders: “You search the Scriptures because you think that in them you have eternal life; it is these that testify about Me; and you are unwilling to come to Me so that you may have life” (John 5:39-40). But Jesus also testified to the authority of the biblical text, down to the smallest letter and to the least stroke of the pen (Matt. 5:18). He said that Scripture cannot be broken (John 10:35).
It is certainly possible to misunderstand the Scriptures. We can intentionally twist the Scriptures. But we cannot put Jesus at odds with the text of Scripture without putting Jesus at odds with himself. To attribute authority to Christ but to deny it to the Scriptures is a contradiction. The Scriptures bear witness to Christ and Christ bears witness to the Scriptures. They both speak of each other and they both speak with the same voice.