Hebrews 10:26

For if we sin willingly after having received the knowledge of the truth, there is no longer a sacrifice left for sins,

2 Peter 2:20-22

For if having escaped the defilements of the world by a knowledge of the Lord and Saviour Jesus Christ, they are again entangled and overcome by them, the last state of those persons is worse than the first.

1 John 5:16

If any one sees his brother commit a sin, not to death, he shall ask, and he will give him life, for those who sin not to death. There is a sin to death; I say not that you should pray for it.

Luke 12:47

And that servant who knew his lord's will and prepared not himself, nor did according to his will, shall be beaten with many stripes;

John 9:41

Jesus said to them, If you were blind you would not have had sin; but now you say, We see, your sin remains.

John 13:17

If you know these things, blessed are you if you do them.

John 15:22-24

If I had not come and spoken to them, they would not have had sin; but now they have no pretext for their sin.

2 Thessalonians 2:10

and with every unrighteous deceit among those who are destroyed, because they received not the love of the truth that they might be saved.

1 Timothy 1:13

who formerly was a blasphemer and persecutor and an injurious man; but I obtained mercy because I did those things ignorantly in unbelief;

Hebrews 6:4-6

For those once enlightened and having tasted of the heavenly gift and been made partakers of the Holy Spirit,

Matthew 12:43-45

But when the impure spirit has gone out of a man, it goes through dry places seeking a rest, and finds none.

Matthew 12:31-32

Therefore, I tell you, every sin and blasphemy shall be forgiven men, but the blasphemy of the Spirit shall not be forgiven men.

James 4:17

He therefore that knows how to do good and does it not, to him it is sin.

Treasury of Scripture Knowledge

Summary

For if we sin wilfully after that we have received the knowledge of the truth, there remaineth no more sacrifice for sins,

Bible References

If

Hebrews 6:4
For those once enlightened and having tasted of the heavenly gift and been made partakers of the Holy Spirit,
Matthew 12:31
Therefore, I tell you, every sin and blasphemy shall be forgiven men, but the blasphemy of the Spirit shall not be forgiven men.
John 9:41
Jesus said to them, If you were blind you would not have had sin; but now you say, We see, your sin remains.
1 Timothy 1:13
who formerly was a blasphemer and persecutor and an injurious man; but I obtained mercy because I did those things ignorantly in unbelief;
2 Peter 2:20
For if having escaped the defilements of the world by a knowledge of the Lord and Saviour Jesus Christ, they are again entangled and overcome by them, the last state of those persons is worse than the first.
1 John 5:16
If any one sees his brother commit a sin, not to death, he shall ask, and he will give him life, for those who sin not to death. There is a sin to death; I say not that you should pray for it.

General references

Matthew 7:27
and the rain descended, and the floods came, and the winds blew and beat on that house, and it fell; and its fall was great.
Matthew 24:21
for at that time there shall be great affliction, such as has not been from the beginning of the world even till now, nor ever shall be.
Mark 3:28
I tell you truly, That all sins and blasphemies with which they blaspheme shall be forgiven the children of men;
Luke 12:10
And every one that speaks a word against the Son of man shall have forgiveness; but he that blasphemes against the Holy Spirit shall not be forgiven.