Hebrews 6:4-8
For it is impossible to arouse people to a fresh repentance when they have once for all come into the light and had a taste of the gift from heaven, and shared in the holy Spirit
2 Peter 2:20
For if after men have escaped the corrupting influences of the world through the knowledge of the Lord and Savior Jesus Christ, they again become entangled in them and are overcome by them, their final condition is worse than their former one.
2 Peter 2:22
What has happened to them shows the truth of the proverb, "A dog returns to what he has vomited up, and a sow that has washed goes back to wallow in the mire."
Jude 1:12
They are stains on your religious meals, where they carouse together, boldly attending to no one but themselves; rainless clouds driven before the wind; leafless trees without fruit, doubly dead, and uprooted;