Hebrews 6:4-6 meaning

The Pauline Author ended the last chapter with the phrase "if God permits," because God sometimes shuts windows of opportunities. The Pauline Author now describes how that can occur. He will tell the Hebrew believers who received this letter that he is confident their window remains open, but clearly this is a warning that they should not hesitate one minute. They need to repent and move toward maturity now, while the opportunity remains.

The Pauline Author warns that there are some believers who once were faithful, who have once been enlightened and have tasted of the heavenly gift and have been made partakers of the Holy Spirit, and have tasted the good word of God and the powers of the age to come (vv 4-5) but then have fallen away (v 6) and stopped living faithfully. Despite this knowledge and experience, they decide to walk away and forsake the path of faithful living. Sadly, at some point their window of repentance closes, and they are not allowed to repent.

This is similar to the children of Israel in Old Testament. They had seen God part the Red Sea and work the miracles in Egypt. They received the word of God from the mountain, the Ten Commandments. They knew God's power firsthand. Finally, when they refused to go into the promised land to which God brought them, God closed their window of opportunity. They were not allowed to possess their inheritance of the land. God still took care of them; they were still His people. But they did not receive God's blessing, even after they changed their minds.

It is important to note that the Pauline Author is writing about genuine believers who fell away. They were partakers of the Holy Spirit, meaning they had received the Holy Spirit upon believing in Christ's death and resurrection and had walked in the Spirit as faithful believers. The word partakers here is from the same word used elsewhere in Hebrews (Hebrews 3:1, 3:14, 6:4); it comes from the Greek word "Metochos," and means "participator," "sharer," or "business partner." 

The believers in this passage are the same as the "holy brethren, partakers of a heavenly calling" in Hebrews 3:1. They are genuine sharers/partakers of the Holy Spirit. They have been spiritually born again and justified in the sight of God by faith in Jesus Christ's sacrifice. The Holy Spirit dwells in them because they have believed in Jesus (Romans 8:9).

But, they have fallen away. The Pauline Author was concerned about this falling away earlier in the book of Hebrews, at the beginning of Chapter 2. "For this reason we must pay much closer attention to what we have heard, so that we do not drift away from it."

He describes believers who abandon their faith as being lost causes with respect to repentance. The Pauline Author writes it is impossible to renew them again to repentance (v 6), to bring them back to a place of repenting of their sin. Whether it is because their window of opportunity is shut, or their hearts are hardened, to renew them again would dishonor Jesus—Since they again crucify to themselves the Son of God and put Him to open shame (v 6). 

Considering the coming judgment when God will judge the hearts of men (Hebrews 4:12-13; Hebrews 12:23) it is hard to consider a worse situation than to be standing before the Judgment Seat of Christ (1 Corinthians 3:11-15; 2 Corinthians 5:10) knowing you have dishonored Jesus by being someone who has lived a life such that he is known as a follower of Jesus, who then turns his back on Jesus and openly shames His reputation.

This is the "salvation" that we don't want to neglect (Hebrews 2:3). We have the opportunity right now to be saved from the effects of sin and be restored to our original created design, which can only be completed through the "suffering of death" and following Jesus Christ our example to the end; rather than fall away and put Jesus to shame, we can become "sons" and "fellow heirs" with Christ whom He leads to glory (Hebrews 2:9-10, Romans 8:17).