I have been trying to prove that Hebrews is an Epistle of Paul. The only evidence against it seems to be a twist on Barnabas in Tertullian, a quote attributed by Eusebius to Origin in reference to an unknown (to me) homily on Hebrews, and the speculation of scholars. But the writings of Origin I do have only confirm multiple times that the Epistle is Paul's and very adamantly in his extant letter to Africanus:
9. . . .
However, some one hard pressed by this argument may have recourse to the opinion of those who reject this Epistle as not being Paul’s; against whom I must at some other time use other arguments to prove that it is Paul’s. . . .
This is written after the hearsay statement of : "Who wrote the epistle is known to God alone" in the timeline but relied on as Origin's only opinion. What's going on, is it a theological issue I should drop for the sake of peace, or am I mistaken?
Thankful for any insights.