If we willfully persist in sin after having received the knowledge of the truth, there no longer remains a sacrifice for sins, but a fearful prospect of judgment, and a fury of fire that will consume the adversaries. Anyone who has violated the law of Moses dies without mercy "on the testimony of two or three witnesses." How much worse punishment do you think will be deserved by those who have spurned the Son of God, profaned the blood of the covenant by which they were sanctified, and outraged the Spirit of grace? For we know the one who said, "Vengeance is mine, I will repay." And again, "The Lord will judge his people." It is a fearful thing to fall into the hands of the living God. (Hebrews 10:26-31, NRSV)
If we sin wilfully after that we have received the knowledge of the truth, there remaineth no more sacrifice for sins, But a certain fearful looking for of judgment and fiery indignation, which shall devour the adversaries. He that despised Moses' law died without mercy under two or three witnesses: Of how much sorer punishment, suppose ye, shall he be thought worthy, who hath trodden under foot the Son of God, and hath counted the blood of the covenant, wherewith he was sanctified, an unholy thing, and hath done despite unto the Spirit of grace? For we know him that hath said, Vengeance belongeth unto me, I will recompense, saith the Lord. And again, The Lord shall judge his people. It is a fearful thing to fall into the hands of the living God. (Hebrews 10:26-31, KJV)
God's pretty judgmental. According to the author, he's given us a chance to get in good with Jesus, but if we don't take it, things won't be pretty.