4 For it is impossible, in the case of those who have once been enlightened, who have tasted the heavenly gift, and have shared in the Holy Spirit,
5 and have tasted the goodness of the word of God and the powers of the age to come,
6 and then have fallen away, to restore them again to repentance, since they are crucifying once again the Son of God to their own harm and holding him up to contempt. (Hebrews 6:4-6)
Many have been confused by this passage, which seems to teach that people can lose their salvation, because it apparently contradicts Romans 8:35-39, which teaches that we cannot. Are the two passages truly in conflict?
The proper approach is to begin by using the clearer passage to explain the more challenging one. In this case, the book of Romans is clearer; in fact, the writer of Hebrews says outright that his topic will be difficult to understand (Hebrews 5:11). Regarding genre, both books are instructional in nature, and so we cannot rely on one over the other based on the style of its literature. Therefore, it also helps to determine the audience of each passage. Romans is a general letter to Roman believers who are not necessarily of Jewish decent, but Hebrews is specifically written to Jewish believers and requires from its readers a familiarity with the book of Leviticus and Judaism.
A key to understanding Hebrews 6:4-6 is to identify who is being discussed. The text describes these people as those who have:
1) once been enlightened,
2) tasted the heavenly gift,
3) shared in the Holy Spirit,
4) tasted the goodness of the Word of God, and
5) tasted the powers of the age to come.
If these two passages are talking about the same group of people, then we do have a contradiction. If not, then we need to determine who these two groups are.
Enlighten means “to make known in reference to the inner life or transcendent matters and thus to give light to or shed light upon.” It has the imagery of a heavenly light granted to an “enlightened one” as through prayer. While this connotes the idea of someone that has some association with God, it does not, however, mandate a relationship with God.
Tasted means “to taste, to eat, or to experience something cognitively or emotionally.” It does not imply possession. This would be an accurate way to describe the Jewish people who had the truth all along yet rejected it, which is consistent with the book’s audience. This could also refer to people that have some experience of God without requiring a completed relationship with God.
There are three major views of this passage possible. It is discussing either
1) genuine believers that fell from grace due to some sin and lost their salvation,
2) the Jewish people who had the truth as God's chosen people, or
3) people who were part of the local congregation of believers but had never been saved and had never enjoyed the benefits and seen the workings of God and His people because they had rejected salvation.
If this passage is discussing true believers that somehow fell away, then one thing is clear: they can never be saved again. Verses four and six declare that it is impossible for these people to be regenerated a second time. In other words, if they can lose their salvation, they can never get it back. While there is not a reference to what the cause of the falling away was, the text seems to imply that it is leaving the church.
Also, if this passage is discussing the loss of salvation, then the next section would not make sense in its context. In Hebrews 6:9-20, the writer explains the certainty of God's promises in order to secure the reality that God will not break His promises and that we are not stronger than God to break His promises for Him. However, when He promises that nothing can separate you from the love of God, what certainty could there be if you can lose your salvation?
If God is the source of our salvation, then we cannot lose it. God would have to take it away. God is the Author and the Finisher of our salvation— “that He who began a good work in you will bring it to completion at the day of Jesus Christ” (Philippians 1:6).
As mentioned previously, the Romans passage is the clearer passage and should be used to interpret the more difficult Hebrews passage. Therefore, based on Romans 8:35-39, Philippians 1:6, and many other clear passages, it would be safe to assume that if God promises to save us, He will keep us. Thus, we cannot lose our salvation.
Then what does Hebrews 6:4-6 mean? And to whom do these verses refer? Evidently, these people have had some relationship to salvation without possessing it completely. It cannot refer to people that gain salvation by God and then lose it. It would make better sense to understand this as a reference either to the Jewish people who had the truth as God's chosen people or to people who were part of the local congregation but had never been saved in the first place. The latter is preferred since the context of Hebrews 5:11-6:3 relates to the local church.
Jesus spoke very often about hypocrisy in His parables. It would be consistent for the writer of Hebrews to address the same issues. Jesus warned of this in the church. We should not be surprised if there was a church whose congregation had unbelievers who thought they were believers but eventually walked away from the faith.
In summary, Hebrews 6:4-6 refers to those that attend a local congregation of believers without being believers themselves. After some time and for whatever purposes, these people leave this local assembly, denying the faith that they once claimed to have. Whether it is a general principle or an absolute truth about what defines falling away, the passage states that because of their understanding of grace and rejection thereof, they can never be regenerated.