This passage contains the third warning in the book (the first two are found on Days 3 and 8). It poses some theological questions and has been the subject of much debate with regard to its proper interpretation. There are those who emphasise that once one is saved by divine choice, one cannot fall into apostasy (abandoning the faith), even though one may fall into sin from time to time. Those who are apostates did not have an authentic experience of the things mentioned in verses 4 to 5. There are others who take the list of Christian experiences and argue that one could still fall into apostasy if one is careless and disobedient. Then there are those who frame the question differently, not having to do with the ultimate security of the believer but with the present need to fully follow Jesus. What is important here is to take our calling to follow Christ with the utmost seriousness and to make every effort not to drift from Christ.

The Hebrews writer gives a harsh warning about those who have left the Christian faith (Hebrews 6:4-6). He describes them as those who were ″once enlightened″, meaning they had understood the gospel of Christ, and probably been baptised. They had ″tasted the heavenly gift″ (Hebrews 6:4). This could refer to participation at the Lord's Supper, the heavenly gift being a reference to Christ (John 4:10; 2 Corinthians 9:15). They had ″shared in the Holy Spirit″ (Hebrews 6:4), probably referring to the new reality of the Holy Spirit in a believer's life. They had ″tasted the goodness of the word of God″ (by reading and hearing it taught and preached; v. 5). They had also tasted the ″powers of the coming age″ (having witnessed the signs, wonders, and miracles performed by Jesus or the apostles, and the transformed lives of many believers; v. 5)-having a ″foretaste of eternity″.²⁴

In spite of all these experiences, if they became apostate there would be no hope for them, because their public rejection would be like crucifying Jesus ″all over again and subjecting him to public disgrace″ (Hebrews 6:6). It would be impossible (v. 4) to bring them back to repentance. The idea is that they would be irredeemably lost. The writer contrasts between a land that produces fruit by drinking the rain that fell on it with another land that only produces thorns and thistles (vv. 7-8). The latter would be cursed and its useless produce burned. God's grace must not be without effect (1 Corinthians 15:10). It should be evidenced by spiritual fruit. This stark warning is meant to shake people out of spiritual slumber before it is too late.

²⁴Barclay, ″The Letter to the Hebrews″, 57