Pieper: "Certainly not!", of deniers of Inspiration

      While reviewing old posts, I ran across a short section from Pieper's essay "Das Fundament" that fulfilled my desire to find the definitive statement by Pieper concerning whether those who deny the Inspiration of Holy Scripture can still be Christians. Here it is in all its forcefulness: 

This raises the question of whether it is still possible for someone to still stand in the Christian faith while denying the divine authority of Holy Scripture. We must say:

 Certainly not

if this denial is given its practical consequence. [emphases mine] Those who do not believe Christ and his Apostles when they testify of the Scriptures: “The Scriptures cannot be broken” [John 10:35] and: “All scripture is given by inspiration of God” [2 Tim. 3:16], he will consequently not believe Christ and the Apostles in what they teach about the forgiveness of sins for the sake of the Blood of Christ.

This teaching has caused me to question whether the "Walkout" men of 1974 actually stood in the Christian faith. It has caused me to question whether Prof. Joel Biermann of today's LC–MS stands in the Christian faith. "Certainly not" if their denial goes to its "practical consequence". Prof. Biermann, in his lectures, speaks of Pieper at times as if he was a good teacher, but this would not have been reciprocated by Pieper given the above statement.