The doctrine of the Roman Church is no longer apostolic. Even in 1854 and 1870 it was still possible to claim to be reaching back to relatively old traditions, or to what were regarded as such. Passages of Scripture could be interpreted so as to be persuasive for faithful Catholics. With the dogma of 1950 [on the Assumption of Mary] this is at an end. The Assumption of Mary is a late legend, and only “conclusion theology” can produce Mary as mediatrix of all graces and coredemptrix.
At work here has been the “theory of development.” This was proposed by J. H. Newman and has been avidly put to use. By the way, one can find it already in [Johann] Möhler. This theory, which is supposed to justify the modern dogmas, is the product of Romanticism and of the 19th century as a whole (the obvious parallels are Darwin and Marx). The picture is that of a seed. At the beginning of the church all its doctrines were contained within the seed, and these then unfolded from century to century. Was not this the case with the doctrines of the Holy Trinity and the Person of the God-man?
To be sure, the understanding of these doctrines progressed through generations. They were, however, already there from the beginning in the apostolic witness [emphasis mine]. The New Testament declares that Jesus Christ is not a creature but the eternal Logos. The New Testament declares that Jesus Christ, ture God and true man, is one Person. What unfolds in the church is the ever deeper understanding of the apostolic words. But nothing can unfold if it is not there in the apostolic words.
-Hermann Sasse, “Apostolic Succession” Letters to Lutheran Pastors No. 41 (1956), We Confess: The Church, p. 89