Many names have been conjectured for the authorship of Hebrews, but the question remains unsolved. The tradition of Pauline authorship is very old and has never been decisively disproved. From the time of Pantaenus (died ca. A.D. 190) it was held in Alexandria that the epistle was in some sense Pauline. Clement of Alexandria thought Paul had written it originally in the Hebrew language and that Luke had translated it into Greek.
On the basis of style, Origen doubted the Pauline authorship but was not willing to set the tradition aside. In a famous statement he admitted that only God knew who had written the book.
The belief in the Pauline authorship of Hebrews belonged chiefly to the East until a later time. Jerome and Augustine seem to have been responsible for popularizing it in the West. In modern times it has usually been felt that the style and internal characteristics of Hebrews rule out Paul as the author. But arguments built on such considerations are notoriously subjective and have also been used to prove highly untenable propostions. Still it must be admitted that when Hebrews is read in Greek and compared with the known letters of Paul, the total impression is that here one meets a spiritual mind clearly attuned to Paul but in subtle ways quite different. This subjective impression, however, would not have prevailed if the early church's tradition had only mentioned Paul.
In fact the other name with early support is that of Paul's former missionary partner, Barnabas. This tradition appeared first in the West in Tertulllian (ca. 160/170 - 215/220). In a polemical passage he quoted from Hebrews and assigned the quotation to an Epistle by Barnabas. Moreover, he did not talk as if this were his own opinion but simply a fact which his readers would know. The view that Barnabas wrote Hebrews was referred to at a later time by Jerome and reappeared in Gregory of Elvira and Filaster, both writers of the fourth century. There is reason to think that in the ancient catalog of canonical books found in the Western manuscript called Codex Claremontanus, the Book of Hebrews went under the name of the Epistle of Barnabas.
The evidence is not extensive, but the fact that it came from the West is perhaps significant. The only geographical reference in Hebrews is to Italy (13:24), and if the tradition about Barnabas is true it is not surprising that it comes from that part of the world. In other respects, Barnabas fits the requirements for authorship of this epistle. Since he was a Levite (Acts 4:36), an interest in the Levitical system, such as the author of Hebrews displayed, would be natural for him. Since he had close ties with Paul, resemblances in Hebrews to Paul's thought would be naturally explained. Moreover, Timothy had been converted in the area of Paul's first missonary journey (Acts 16:1-3) and was therefore most probably known to Barnabas. If Paul were dead at the time of the writing of Hebrews, it would not be surprising if Timothy were to join Paul's former companion (Heb. 13:23). The rift between Paul and Barnabas (Acts 15:37-39) had long since healed and Paul had later spoken warmly of Barnabas' cousin Mark (cf. Col. 4:10; 2 Tim. 4:11).
Of course authorship by Barnabas cannot be proved, any more than authorship by Paul can be disproved. But it has more to commend it than the other alternative suggestions. Among these it may be mentioned that at one time or another the names of Clement of Rome, Luke, Silvanus, Philip the Evangelist, Priscilla, and Apollos have been offered as possible authors. In particular the name of Apollos has found favor with some modern writers. The suggestion is often traced to Martin Luther. But the evicence is tenuous and does not include the early traditional support that the proposal Hebrews was written by Barnabas does. On balance this seems like the best conjecture. If Hebrews were actually authored by Barnabas, then it can claim apostolic origin since Barnabas was called an apostle (Acts 14:4, 14). In any case its divine authority is manifest.