"...Jesus, the Author and Completer of our faith" (Heb. 12:2).
The Letter to the Hebrews is the only New Testament book to assign no author. We don't know who wrote it. Guesses include Barnabas, Luke, Clement of Rome, and Aquila and Priscilla. Luther suggested Apollos, mentioned for the first time in Acts 18:24. "But who wrote the epistle," said Origen of Alexandria, "God only knows certainly." But from this, two things may be said.
One is, isn't it something that the only book not to say who its author is, is the one book to say who the Author of our faith is? That's the authorship that matters. "Let us, through endurance, go on running the race set before us, looking to Jesus, the Author and Completer of our faith." And for the perfect commentary on "Author and Completer," use Philippians 1:6: "He who began (authored) a good work in you will bring it to completion."
Two is, humility. Whoever wrote Hebrews had a lot to be proud of: understanding, eloquence, heart. It is said that the letter displays the finest Greek in the New Testament. And yet they wanted to remain anonymous. T.S. Eliot wrote: "Many are engaged in writing books and printing them. Many desire to see their names in print." When was the last time you saw the most beautiful book but without the author's name? Answer: The Letter to the Hebrews.
Seek to do beautiful and blessed things, but to receive no earthly credit.