Donald Hagner is an outstanding biblical scholar and he has spent many years studying the book of Hebrews. This is an excellent expositional commentary (based on the NIV) which deals with all the issues in a very clear and understandable way, and does so in a non-technical way. Hagner does a great job of bringing out the themes of the Supremacy and Sufficiency of Christ and He touches upon the main themes: Christ as Ultimate Revelation, Christ is Greater than Moses, He is Superior to Aaron, and His Priesthood (in the order of Melchizedek) is superior to that of the Levitical Priesthood. He deals with all the issues, including the difficult passage in Hebrews 6: 4-5 (apostasy); his take on Heb. 6: 4-6 is that this passage is dealing with genuine Christians, who prove that their faith is genuine through perseverance in the faith. (Those who fall away were not genuine believers to begin with). He does not believe in the hypothetical argument. In the section on Heb. 4: 1-16, Hagner sees the "rest" as both present and future.
I liked how the NIBC commentary is organized. Hagner provides the reader with a general overview and explanation of each chapter in the book of Hebrews. Then at the end of every chapter, there is the "Additional Notes" section which provides further explanations of the specific words and phrases in Greek. I found the Additional Notes to be very helpful.
If you want a solid evangelical commentary that is rich in biblical insights and is accessible to both layperson, seminary student, and pastor alike, I would highly recommend this commentary. It is a good starter. I would highly recommend you purchase Donald Hagner's fuller overview of the book of Hebrews "Encountering the Book of Hebrews" in the EBS series (ISBN: 978-0-8010-2580-8). Hagner goes into greater detail in explaining the background, themes, and passages in Hebrews.
Other recommended commentaries on Hebrews from an evangelical perspective:
Expositional: F.F. Bruce, The Epistle to the Hebrews (New International Commentary on the New Testament), Eerdmans, 1990. John MacArthur, Hebrews, Moody, 1983.
Technical: Paul Ellingworth, The Epistle to the Hebrews, (New International Greek Testament Commentary), Eerdmans, 1993; William Lane, Hebrews (2 volumes The Word Biblical Commentary), Word, 1991.
