Should I Be Scared of Hebrews Chapters 6 and 10?

Should we be afraid of verses like this?
For it is impossible, in the case of those who have once been enlightened, who have tasted the heavenly gift, and have shared in the Holy Spirit, 5andhave tasted the goodness of the word of God and the powers of the age to come, 6and then have fallen away, to restore them again to repentance, since they are crucifying once again the Son of God to their own harm and holding him up to contempt. – Hebrews 6:4-6