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1Therefore leaving the doctrine of the first principles of Christ, let us press on to perfection -- not laying again a foundation of repentance from dead works, of faith toward God, 2of the teaching of baptisms, of laying on of hands, of resurrection of the dead, and of eternal judgment. 3This will we do, if God permits. 4For concerning those who were once enlightened and tasted of the heavenly gift, and were made partakers of the Holy Spirit, 5and tasted the good word of God, and the powers of the age to come, 6and then fell away, it is impossible to renew them again to repentance; seeing they crucify the Son of God for themselves again, and put him to open shame.
Hebrews 6:1-6 (WEB)