What does confessional mean?
The word confession has different meanings. One is an admission of sin, which might come to mind at first, but that is not our concern here. Rather it is a written witness or statement of faith. A confessional church subscribes to a confession, meaning the confession will guide its teaching and practice, or for the individual, their faith and life.
For the Lutheran, it means we subscribe to the Book of Concord as being a faithful witness to what the whole of Scripture teaches.
Why is it important to us to be Confessional Lutherans?
Why do we need Creeds/Confessions?
If we have God's breathed Word in the Scriptures (2 Tim 3:16), why do we need human summaries in Creeds and Confessions? Because so many Christian denominations exist and there is marked disagreement on foundational areas.
But why are there so many differences of interpretation?
Given our sinful nature, is there any hope of arriving at a right interpretation of Scripture?
Yes. Humans can draw true conclusions about physical Creation by experimental verification - Creation is consistent and self-authenticating. So too the Scriptures ( 2 Tim 3:16) - not by experiment but by allowing Scripture to interpret Scripture. By comparing an interpretation against the whole of Scripture. By using clear passages to interpret difficult ones. By trusting its authority, even when it defies your reason. Thus the old sinful nature which desires to use magisterial reason to judge the text is neutralized..