The author of Hebrews makes a quite frightening warning to his audience in Hebrews 6:4-6 about the dangers of turning away from the faith.
4 It is impossible for those who have once been enlightened, who have tasted the heavenly gift, who have shared in the Holy Spirit, 5 who have tasted the goodness of the word of God and the powers of the coming age 6 and who have fallen[a] away, to be brought back to repentance. To their loss they are crucifying the Son of God all over again and subjecting him to public disgrace.
There are so many debates here about the meaning of words, whether the people described are “truly” saved, whether this is about people on the verge of faith, it intersects with your views of Arminianism and Calvinism, plus whether the passage is merely describing a hypothetical situation.
What do I think? Well, it’s a hard one, and it pushes the integrity of my Calvinism almost to breaking point. I mean, I do kind of like my perseverance of the saints, but commitment to a theological system should not happen at the price of bad biblical exegesis.