Hebrews is a complex and challenging book to study. It consists of only 13 chapters, but those chapters brings the believer into new depths and love for Christ and God. To understand some of the context of Hebrews some intro material might be helpful:

Author: unknown > some suggest Paul, others Apollos, the suggestions are not few and in no way unimaginative. But since no one knows for sure, the best response would be probably Paul, but really unknown.

Audience: this book was written to Jewish Believers and to Hellenistic Greek Jews.

Purpose: It is layered in its purpose. (1) Show the superiority of Christ over all people and things (2) encourage believers to maturity in the faith (3) keep believers, especially the Jewish believers, from relapsing back into the customs and requirements of Judaism.