For it is impossible for those... — The connection of thought has been already explained (Hebrews 6:3); the general meaning will be examined below (Hebrews 6:6). It will be seen that the greater part of this long sentence is dependent on the word “renew” in Hebrews 6:6, “It is impossible to renew again unto repentance those who were once,” &c.
Those who were once enlightened. — This metaphor is introduced again in Hebrews 10:32; neither there nor here does the context contain any notice or expansion of the figure. In that passage, however, it is applied generally to all who are addressed, and includes everything that was involved in the reception of the Christian faith. This inclusive application of the term (familiar from prophecy, from our Lord’s own words, from Apostolic usage; see Acts 26:18; Ephesians 1:18; 1 Peter 2:9) throws light on the construction of the verse before us. As the words stand in the Authorised version, “enlightened” is but the first term of a series; but it is far more probable that the clauses which follow should be regarded as explanatory of the enlightenment itself: “... those who were once enlightened, having both tasted... and been made partakers... and tasted...”
Tasted of the heavenly gift. — On the first word, see the Note on Hebrews 2:9. From the clear parallelism which exists between these verses and Hebrews 2:3-5 we may infer that the “salvation” offered in the gospel (Hebrews 2:3) is intended by this “gift.” It is a gift which belongs to heaven (comp. Hebrews 1:14), bestowed by Him from whom has come the “heavenly calling” (Hebrews 3:1; Hebrews 2:10). The following words at once recall Hebrews 2:4, “gifts (distributions) of the Holy Ghost.”