The plain and the simple of it is, Hebrews was pertaining to the "Hebrews" and not to the Body of christ.
Hey Grosnick,
I don't think that your statement is true.
I think there are clues in the book that show that the book of Hebrews was probably written to Jewish Christians...
Hebrews 3:12-14: "Beware, brethren, lest there be in any of you an evil heart of unbelief in departing from the living God; but exhort one another daily, while it is called “Today,” lest any of you be hardened through the deceitfulness of sin.
For we have become partakers of Christ if we hold the beginning of our confidence steadfast to the end"
...and they have suffered for the Faith...
see Hebrews 10:32-36.
Peace.