Proper 23 • Hebrews 3:12–19 • October 11, 2015

By Joel Biermann

This text hardly ranks among the most popular or familiar of those gathered in the pericopes; but with its stern warnings, emphasis on Christian responsibility, and explicit OT imagery, it serves nicely as a representative of the entire book, and offers some interesting opportunities for the preacher.

These vital points can be gleaned from these verses:

An evil unbelieving heart is avoidable. This is not quite the axiomatic statement that it might seem. With our right emphasis on divine monergism and the gift of faith as entirely God’s work from start to finish, it is tempting to read against the text and insist that perseverance in faith is God’s business, period. But, that is clearly not the author’s point. Without diminishing God’s sovereign work in our lives (he is a living and active God who impacts us directly), we must teach and insist that each Christian is fully responsible for resisting sin and curbing unbelief, or more literally, unfaith. A related question, worth consideration and exploration, but without a clear answer, is the precise relationship between a sinning heart and an unbelieving heart. The writer to the Hebrews doesn’t seem opposed to treating them as synonyms.

The means of preventing unfaith, or more exactly, apostasy, is the giving and receiving of mutual encouragement. It is perhaps self-evident, but by no means widely admitted or practiced, that such a remedy demands active communities of faith. “One anothers” exist only in such communities. The power of Christian edification to sustain faith enjoys scriptural and even confessional support, but it’s too often given short shrift in deference to the more potent means of absolution—preaching and sacrament. This text provides the preacher the chance to propound the great gift of “one another” and the sustenance that comes when we not only receive but also deliver words of edification and encouragement.

Sin is deceitful. Again, while the tautological aspect is evident, the realities of parish ministry expose the failure of both people and pastors to more honestly recognize and admit this truth. Sin becomes altogether too common and familiar and so “safe.” The writer to the Hebrews screams the contrary alert: Sin kills. His pointed illustration from Exodus history is particularly poignant. It is unnerving to recall that the failed generation of Israelites had all heard, as well as seen, the concrete actions of God on their behalf, and nevertheless succumbed to the lure of sin, evil, and unfaith. Corpses and bleached bones in the wilderness show the score. Sin is never what it seems. No sinner ever has his sin under control. Imperceptibly, yet certainly, arteries harden until the fact is suddenly manifest: a dead body via heart attack or stroke. Sin works the same hardening effect on faith. Believers can also grow old and hard and succumb suddenly to unfaith. What a Christian “used to do” is irrelevant. What matters is what is done today. No one is immune from the deceit and danger of sin.

The time to act is today. The writer reminds us that hackneyed truth may still be truth: yesterday and tomorrow are beyond our grasp, only today matters. Thus, the day to encourage is today—an ever-present task. Ultimately, of course, it is the long succession of todays lived faithfully that eventuates in God’s eternal rest.

Suggested Outline:

“What day is it?

I. The immediacy of the threat.

A. Warning! Watch your heart, today.

1. God gives faith.
2. You need to maintain it.

B. Warning! No one is exempt from sin’s deceit.

1. Israel heard God’s grace and still fell.
2. Yesterday’s faith does not save a person today.

II. The immediacy of the work to meet the threat.

A. Encourage each other right now.

1. This is a sure defense against unfaith.
2. To do this requires a community of faith.

B. Every “today” becomes part of a succession of todays.

1. This creates a legacy.
2. This ends in eternity (which is a continual “today”).

Conclusion: “What day is it? It’s today, so go and do the work of today.”

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