If justification and sanctification are not separate, the Bible is nothing more than a book of confusion. (source)
Or rather, If justification and sanctification are not separate, the Pauline Corpus is nothing more than a book of confusion. Its not like justification by faith and not by works is a theme of the Bible as a whole, because it isn’t. The whole issue is that Protestantism tosses all the book outside the Paulina and redefines “Bible” to mean “Paulina.” Its pure Marcionism. [For those who don’t understand the reference, Marcion’s Bible consisted only of 10 Pauline epistles which he called The Apostolikon and a shortened Luke, simply called The Gospel.]
And as far as the Pauline Corpus being a book of confusion, that’s essentially what Peter tells us:
15 Regard the patience of our Lord as salvation; even as our beloved brother Paul also, according to the wisdom given to him, wrote to you; 16 as also in all of his letters, speaking in them of these things. In those, there are some things that are hard to understand, which the ignorant and unsettled twist, as they also do to the other Scriptures, to their own destruction. (2 Peter 3:15-16 WEB)
Protestants will be forever confused because they treat Paul as primary scripture, whereas logically (considering his incomprehensibility) he can only be treated as supplementary scripture, as a sort of apocrypha or deutero-canon.
That is in fact how he was treated for the first 3 centuries of the church. Prior to Augustine, the gospels and Old Testament were the primary scripture, and Paul was only brought in to back them up where Paul was in agreement with them. Never did they take Paul seriously where he does or at least seems to contradict them. He was only used as a supplement.
Up until Augustine, Paul was used in the same way that Jerome would later suggest the apocrypha should be used: only to support doctrines plainly taught in the primary scripture, but never to build doctrines from directly.
So the church “fathers” quoted Paul to support the importance of baptism, or the importance of faith, the fact of the resurrection. Never, however, did they quote him on predestination or any of that type of nonsense. Never did they take justification by faith apart from works seriously, aside from meaning that circumcision and keeping the sabbath are not required. Never did they use it against baptism. Because Paul was apocrypha, simply supplemental scripture, until Augustine. Post-Augustine, however, the gospels are treated as supplemental and Paul as primary! This is the heresy of Augustine, and unfortunately it continues in both Catholicism and Protestantism.
And the same actually goes for the general epistles too. They were only supplementary as Paul is. But of course, everyone still treats them as such. Isn’t that interesting?