The author of Hebrews compares Jesus to angels. By pointing us to the Old Testament Scriptures, the author shows us that Jesus has a superior nature and superior office to the angels.
The author’s use of Old Testament Scriptures teaches us that we should be more diligent in using Scripture when we are offering encouragement to fellow believers who are struggling and when we are speaking with those who don’t believe. The Holy Spirit will use the reading of the Word of God in those conversations to change hearts and lives.