The material below substantiates that, notwithstanding doubts that have arisen especially in the modern age, the most-ancient historical sources identified Paul as the author of the book of Hebrews.
from an anonymous session with ChatGPT the week of August 25, 2025:
The oldest extant full or partial New Testament manuscripts we have that include Hebrews, the book before it, and the book after it show it to be placed after Romans or 2 Thessalonians. (It is unknown whether P46 was originally an entire NT or only a collection of Paul’s letters.)
200 AD (P46): Romans → Hebrews → 1 Cor
↑ Earliest known placement
300s–400s (Codices: Vaticanus, Sinaiticus, Alexandrinus): Romans → … → 2 Thess → Hebrews → 1 Tim
↑ Common Greek tradition
400s (Vulgate): Romans → … → Philemon → Hebrews
↑ Western (Latin) order
1500s (Luther): … → Hebrews → James → Jude → Revelation
↑ Disputed but included
Modern Bibles: Romans → … → Philemon → Hebrews → James
↑ Settled canonical order
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