Therefore we must pay much closer attention to what we have heard, lest we drift away from it. Hebrews 2:1

We have seen that there is an overall structure to whole book

It is a wave-like pattern that alternates between revelation and warning
– the first revelation came in chapter 1,
• and now in chapter 2 we have the first warning
◦ the warning sections can be severe
◦ but the writer also softens them softened with encouragements