Hebrews 6:4-6

It is impossible to restore an apostate. For once a person has come into God’s light, and tasted the gifts of the heavenly realm, and has received the Holy Spirit, and feasted on the good Word of God, and has entered into the power of the age that is breaking in, if he abandons his faith, there is no use even trying to lead him to repentance. By their sin of apostasy they re-crucify the Son of God, and have publicly repudiated him.