The author begins with a healthy fear: since the promise of entering his rest remains, none of the readers should seem to have fallen short. The good news was preached to them, as it was to Israel, but the message did not benefit those who heard it because they were not united by faith with those who obeyed. Those who believe enter the rest, as God said in Psalm 95. That rest is not only the rest of Canaan: God rested from his works at creation, and if Joshua had given Israel the final rest, God would not have spoken of another day later, the day called today. So a Sabbath rest remains for the people of God, and whoever enters it rests from his works as God did from his. Therefore they must strive to enter that rest, so that no one falls by the same example of disobedience.
Next comes a description of the word of God. It is living and active, sharper than any two-edged sword, piercing to the division of soul and spirit, of joints and marrow, and discerning the thoughts and intentions of the heart. No creature is hidden from God's sight; all are naked and exposed to the eyes of him to whom we must give account.
The chapter closes with a turn toward encouragement. We have a great high priest who has passed through the heavens, Jesus the Son of God, so we should hold fast our confession. He is not a high priest unable to sympathize with our weaknesses: he was tempted in every way as we are, yet without sin. Let us then approach the throne of grace with confidence, to receive mercy and find grace to help in time of need.