In this discussion, I am using the term form, quite broadly, to denote those features of the biblical text that express (in additional to their propositional content) a mood or manner about the propositional content. This means, therefore, that I am not using form in any sort of strict literary sense. Let me explain why that distinction is important.
I am making the claim that the Bible’s form (and not merely the Bible’s content) is the authoritative standard for the faith and practice of the believer (and of the churches). If I were using form in a strict sense, I would be demanding that, for instance, Hebrew poetical structures be used in our churches for hymnody. But this is not my claim.
Let me offer a claim parallel to mine, as an illustration. I do not believe that good theology demands that we merely restate the very language of Scripture (in Greek and Hebrew). I believe that theology can be rightly called good even if (for instance) it is in English, or if it uses terms not found in the Bible, or if it offers legitimate deductions from the Bible. This flexibility, however, does not mean that all theology is permissible. Identifying the theology that is good is not always easy; nonetheless, there is a genuine kind of faithfulness to the content of Scripture that is essential for any theology to be acceptable.
In the same way, biblical form is authoritative for the church not because the church must simply parrot those literary forms, but in such a way that the forms chosen for expression of biblical truths are also faithful to the mood and manner of the biblical forms. So, for instance, when we preach about or sing about a prophetic oracle of judgment, we must do so in a manner (today) that expresses and incites the same kind of mood that Jeremiah intended to incite. To be faithful to Jeremiah’s content, but to betray his manner, is also an unfaithfulness to the authority of Scripture.