Hebrews 6:4

For it is impossible for those who were once enlightened, and have tasted of the heavenly gift, and were made partakers of the Holy Ghost,

We must 'go on toward perfection;' "For," if we fall away, after having received enlightenment, God will not "permit" - it will be impossible to renew us again to repentance. But see Luke 18:27.

For those -`in the case of those.' For those - `in the case of those.'

Once enlightened - once for all illuminated by the Word of God, taught in connection with 'baptism' (to which, in Hebrews 6:2, as once for all done, "once enlightened" here answers) (cf. Ephesians 5:26). This passage originated the subsequent application of 'illumination' to baptism. Illumination was not supposed inseparably to accompany baptism. Chrysostom says 'Heretics have baptism, not illumination: they are baptized in body, not enlightened in soul: as Simon Magus was baptized, but not illuminated.' That "enlightened" here means knowledge of the truth appears from comparing [ footisthentes (G5461)] "illuminated," Hebrews 10:32, with the corresponding Heb. 6:26 , "knowledge of the truth."

Tasted, [for themselves: geusamenous (G1089)]. As "enlightened" refers to sight, so taste follows (1 Peter 2:3).

The heavenly gift - Christ given by the Father: revealed by the enlightening word: bestowing peace in the forgiveness of sins and the Holy Spirit (John 3:16; John 4:10; John 6:32; 2 Corinthians 9:15): answering to "baptisms" (Hebrews 6:2: cf. Acts 22:16) and "the Son of God" (Hebrews 6:6): distinct from "the Holy Spirit" in the next clause, who also is "the gift of God" (Acts 8:20).

Made partakers of the Holy Spirit - distinct from, though inseparably connected with, "enlightened," "tasted of the heavenly gift," Christ: answering to "laying on of hands" after baptism, then generally accompanied with the impartation of the Holy Spirit in miraculous gifts.