Sola scriptura took aim at two different opponents at once, and Lutheranism has kept both fights distinct ever since. Against Rome, the issue was whether an unwritten apostolic tradition, interpreted authoritatively by pope and council, carried the same binding force as the written Bible. The Council of Trent answered in 1546 that scripture and tradition were to be received with equal reverence, a two source view the Reformers rejected as placing the church's word above God's. Lutheranism did not respond by discarding tradition altogether. The Book of Concord is itself a tradition, a set of confessions Lutherans bind themselves to teach and preach by, but its authority is explicitly derivative: it binds because it is judged, on scriptural grounds, to teach what scripture teaches, not because a teaching office declared it so.
Against the radical reformers, the argument ran the other way. Some Anabaptist and spiritualist writers pushed toward a looser reliance on individual reading that set the believer's own sense of scripture against every inherited creed and even against orderly public ministry, trusting immediate inner conviction as much as the text. Lutheran confessional writing resisted this too, insisting scripture is to be read within the church's teaching office and its historic creeds, not against them. The distinction is easy to blur from outside the tradition, since both positions can sound like plain biblicism, but confessional Lutheranism has consistently placed itself between the two, subordinating tradition to scripture without dissolving the church's teaching authority into private judgment.