What does Hebrews 6:12 mean?

This passage switches tone from the ominous warning of verses 6–8 to a more reassuring view. The good works being done by these persecuted Jewish Christians were good evidence that they had a sincere, living faith. Even in that reassurance, however, there is still room for improvement and instruction. Specifically, the readers need to pursue growth in their sense of hope—their trust, reliance, and confidence—in order to completely fulfill their calling.

Hebrews 5:11 criticized the spiritual condition of these same believers, calling them "dull of hearing." The Greek term used there, nōthroi, is exactly the same word used in this verse to warn against becoming "sluggish." The same general idea applies to both, which is laziness—a lack of effort or concern. While that specific problem does not seem to affect these Christian brothers and sisters, yet, it needs to be kept in mind for the future.

Prior verses made a point of warning about laziness in our approach to Christian truth. Here, the warning seems to be about laziness in our approach to our own hope. We need to guard our confidence in Christ, especially in a world which attacks it and persecutes those who believe. Rather than putting ourselves at risk of "falling away," we need to diligently seek our faith. This is not meant to earn our salvation, but simply to maintain our assurance that we're following the will of God.

Continuing this encouragement, the next passage gives the example of Abraham, who exhibited this very form of patient faith.