Hebrews 2:3
how shall we escape, if we neglect so great salvation, which at the first was spoken through the Lord, and was confirmed to us through those who heard him,
Hebrews 6:6
and have fallen away, should again be renewed to repentance, since they crucify to themselves the Son of God afresh, and put him to open shame.
Hebrews 9:28
so also Christ having been once offered up to bear the sins of many, will appear the second time, without sin, for the salvation of those who are waiting for him.
Hebrews 10:26-29
For if we sin willingly after we have received the knowledge of the truth, there no longer remaineth a sacrifice for sins;
Hebrews 12:25
See that ye refuse not him who speaketh. For if they did not escape, who refused him who spoke his will on earth, much more shall not we, if we turn away from him who speaketh from heaven;