Hebrews 10:28

not forsaking our own assembling together, as the custom of some is, but exhorting one another, and so much the more as you see the Day approaching.

For if we sin willfully after we have received the knowledge of the truth, there remains no more a sacrifice for sins,

but a certain fearful expectation of judgment, and a fierceness of fire which will devour the adversaries.

How much worse punishment do you think he will be judged worthy of who has trodden under foot the Son of God, and has counted the blood of the covenant with which he was sanctified an unholy thing, and has insulted the Spirit of grace?

For we know him who said, “Vengeance belongs to me. I will repay,” says the Lord. Again, “The Lord will judge his people.”

It is a fearful thing to fall into the hands of the living God.