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Hermeneutics is the study of the principles and methods of interpreting the text of the Bible. Trajectory hermeneutics or redemptive-movement hermeneutics (RMH) is a hermeneutical approach that seeks to locate a topic within the text and follow its “trajectory” throughout Scripture to see how God was slowly working to “redeem” that topic and move the world toward a better standard. Once the trajectory is identified, it is then extrapolated into the present-day world to see how we should view that same topic today.
The first job of the trajectory hermeneutic or redemptive-movement hermeneutic is to see the subject from the point of view of the original recipients. The subject is then traced through a progressive “trajectory” through history (or at least through the biblical witness). Finally, the subject’s trajectory is assumed to continue beyond the New Testament to affect issues in our world today.
The issue of slavery is often used to illustrate trajectory hermeneutics or redemptive-movement hermeneutics. In the first parts of Scripture, slavery was accepted as a normal part of culture, even among the Hebrews. However, the Mosaic Law limited what could be done to slaves and provided for treatment that was humane, compared to what the surrounding cultures allowed. Such rules show the “trajectory” that God intended to take regarding slavery. In the New Testament, masters were admonished to treat their slaves well (Colossians 4:1), and Paul referred to a slave as his brother in Christ (Philemon 1:16). This continues the “trajectory” of redemption. According to trajectory hermeneutics, we can follow the path that Scripture naturally set us on and conclude that God desired the emancipation of slaves. While no Scripture exists that abolishes slavery outright, we can infer from the “redemptive movement” within Scripture that God’s will was that slavery end, to the betterment of society. By extending the trajectory begun in Scripture, we can arrive at a logical conclusion.
So we see that redemptive-movement hermeneutics or trajectory hermeneutics is involved mainly with societal ethics. It attempts to provide answers for those modern issues that the Bible does not directly address by finding the “redemptive spirit” behind the actual text of Scripture and “working out” or developing the ethics contained in seed form in the Bible. Other issues tackled by proponents of trajectory hermeneutics include homosexuality and the role of women in ministry.
By its very definition, trajectory hermeneutics or redemptive-movement hermeneutics goes beyond what Scripture says. It relies on a “logical extension” of Scripture for its application in modern-day life. Proponents of the redemptive-movement hermeneutic do not see their approach as conflicting with the more traditional, grammatical-historical method of exegesis.
Trajectory hermeneutics or redemptive-movement hermeneutics contains some dangers in its approach to Scripture, however. One has already been mentioned—following a “trajectory” of a biblical principle goes beyond what Scripture actually says about an issue. If the biblical ethic was somehow “incomplete,” as redemptive-movement hermeneutics says, and must be “developed” outside of Scripture, then who gets to plot the “trajectory,” and where does it stop? If logic leads to an “ultimate ethic” that differs somewhat from the explicit teaching of the Bible, then is that “ultimate ethic” better than the Bible’s ethic? If so, haven’t we replaced the authority of Scripture with our own reason?
Another weakness of trajectory hermeneutics or redemptive-movement hermeneutics is its strong reliance on a knowledge of the culture in which Scripture was written. In order to chart the “trajectory” of an ethical issue, the Bible student must understand how the Bible’s teaching conflicted with the various cultures throughout history. But such knowledge is not always available, and, even when it is, it’s not accessible to everyone, and so it cannot be viewed as necessary for understanding the scriptural message. The grammatical-historical method of interpretation also seeks to understand the cultural milieu in which the Bible was written, but simply as a matter of good exegesis.
Better than trying to guess where the Bible “might have been headed” is studying what the Bible actually says.