Hebrews 3,4

12. Take care, brothers, lest there be in any of you an evil, unbelieving heart, leading you to fall away from the living God.
1. Therefore, while the promise of entering his rest still stands, let us fear lest any of you should seem to have failed to reach it.

Hebrews 6

4. It is impossible in the case of those who have once been enlightened, tasted the heavenly gift, become partakers of the Holy Spirit,
5. tasted the good word of God and the miracles of the coming age,
6. and then have fallen away, to renew them again to repentance, since they are crucifying the Son of God for themselves all over again and holding him up to contempt.

Hebrews 10

26. For if we deliberately keep on sinning after receiving the knowledge of the truth, no further sacrifice for sins is left for us,
27. but only a certain fearful expectation of judgment and a fury of fire that will consume God’s enemies.
28. Someone who rejected the law of Moses was put to death without mercy on the testimony of two or three witnesses.
29. How much greater punishment do you think that person deserves who has contempt for the Son of God, and profanes the blood of the covenant that made him holy, and insults the Spirit of grace?

Hebrews 12

15. See to it that no one comes short of the grace of God, that no one be like a bitter root springing up. and causing trouble, and through him many become defiled.
16. And see to it that no one becomes an immoral or godless person like Esau, who sold his own birthright for a single meal.
     
25. Take care not to refuse the one who is speaking! For if they did not escape when they refused the one who warned them on earth, how much less shall we, if we reject the one who warns from heaven?

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