If the unbelievers are Jews that “fall away” by returning to Judaism, how can the writer say that they are turning away from the living God? The Jews do recognize God. The point is that Judaism no longer presents the true revelation from God, it is inferior to the revelation that comes through Jesus in “these last days” (from 1:1-3).
A possible solution to the possibility of unbelief in the community of believers is that the “encourage each other daily.” The “daily” exhortation underscores the meaning of the word, this is an active effort on the part of the community of believers to help each other with their Christian walk. There is a positive aspect to this word (encouragement), but also a negative aspect, a pushing toward spiritual excellence which may take the form of a shove!
In the modern church we tend to think of the pastor as a professional exhorter, as long as he doesn’t get too personal or call during dinner or the football game to exhort us. Half an hour on Sunday is fine for most people (just don’t mention “sin”). This text says that the community ought to encourage the community. Mutual encouragement, but also exhortation – a sort of positive peer-pressure that encourages growth and development of a deeper relationship with God and each other.
The writer of Hebrews describes a whole church talking to each other and trying to keep each other from sin, a network of accountability that is virtually unknown in the modern church.
What are the people to encourage? That we not be deceived by sin and harden our hearts. Sin is deceitful, it is seductive. Satan does not appear as a slobbering evil dragon demanding your soul, he appears as an angel of light, a really nice guy with a good plan to help humanity, or maybe to help your family. He takes the truth and twists it into a sin that looks pretty good! Sin is a subtle deception, those are the best kind.
But if your community of believers is daily encouraging you not to harden your heart, it is much easier to do the right thing and avoid sin. I am not sure modern Christian communities are very good at this encouragement. On the one hand, they can become very legalistic and judgmental, even demanding of their members (to the point of being more like a cult than the Body of Christ). On the other hand, some churches are so lax in this sort encouragement that there is no call to deal with the flesh, nor any preaching on sin in the life of the believer. As they say these days, “it’s all good.”
It is not all good, it never was. Believers need to return to this sort of mutual encouragement for the building up of the Body of Christ. Does is local church always an community? How might this section of Hebrews be used to transform personal relationships?