All the Old Testament prophets spoke of the coming Messiah, but now that He has appeared, what He says is even more authoritative because He is God's final Word. In keeping with the theme of Hebrews, that Jesus Christ is preeminent over all things, we start with who He is as God's final revelation, the Creator, and our Redeemer. If He is God's full and final revelation, we should more diligently heed what He says. Jesus has promised a rewarding future in the kingdom if we do not neglect our spiritual progress. On the other hand, there will be serious consequences for those who do not mature. As believers, we must listen to Him. For more context, you can see GraceNotes no. 15 about interpreting Hebrews https://www.gracelife.org/resources/gracenotes/?id=15&lang=eng. Charlie unpacks this passage at Bayside Community Church in Tampa.