From an essay in the ESV Study Bible:
SCRIPTURE READING IN PUBLIC WORSHIP
The Bible, as holy Scripture, is the only certain source of God's words in the entire world. Paul's statement that "All Scripture is breathed out by God" (2 Tim. 3:16) means that all the words of the Bible are God's words to us. Therefore if we want to hear our Creator and Lord speaking to us, we must continually give attention to the authoritative words of the Bible. This means that the Bible must be the only true foundation and constant guide for all that we do in the life of the church, and the Bible must be central to all that happens in preaching and public worship. . . .
God's Word deserves great reverence from his people. Isaiah writes, "But this is the one to whom I will look: he who is humble and contrite in spirit and trembles at my word" (Isa. 66:2). Therefore when Scripture is read aloud in a worship service, the reader and the congregation should take care to convey the reverent attention that Scripture deserves.
From its earliest days the church gave primacy to the reading of Holy Scripture, as seen in the apostle Paul's aforementioned charge to Timothy to devote himself to "the public reading of Scripture," as well as Justin Martyr's account of the apostolic church's practice of reading "the memoirs of the apostles and writings of the prophets . . . as long as time permits." The regular custom soon was to have two extended public readings, one from the OT and one from the NT. . .
The Bible's use in preaching and public worship should be in such a way as to result in a Christ-exalting service of the Word. This requires work by the preacher and the leaders of the congregation, so that God's Word is read to his glory, the sermon is derived from the faithful exposition of the text reading, and the reading and preaching of the biblical passage is set in the context of songs and hymns and programs that are redolent with the substance of God's holy Word.