Take “complementarianism,” for example. The term was introduced in the 1980s to describe the idea that men and women are “equal but distinct” in their roles. But what does that mean? Interpretations vary widely. In some circles, complementarianism emphasizes traditional male authority, such as restricting eldership to men. In others, it’s softened to allow practices like women teaching in mixed-gender settings, as long as they do so under male oversight. This flexibility in definition has created room for gradual shifts, sometimes moving closer to functional egalitarianism. Russell Moore has even critiqued this, noting how many evangelical marriages may claim to be complementarian but operate in ways that lean egalitarian in practice. Similarly, terms like “leadership” often borrow ideas from the corporate world—like “vision casting”—which risks overshadowing the biblical model of shepherding and shifting authority away from God’s design toward human expertise.

Ambiguity also opens the door for cultural accommodation. Liberal theology, for instance, has long been marked by its tendency to adapt Christian doctrine to align with modern intellectual trends. Words like “inclusivity” or “social justice” often retain a Christian veneer but move away from orthodox foundations. Consider “progressive Christianity,” which frequently reinterprets sin as systemic oppression rather than personal moral rebellion. Gary Dorrien, a theologian who studies liberalism, has pointed out how ambiguous language allows modern ideas—like naturalism or secular humanism—to quietly infiltrate theology, even as it retains familiar Christian terminology. It’s a strategic kind of vagueness that makes these shifts seem less radical than they are.

This lack of clarity also influences how Scripture itself is interpreted. Ambiguous terms encourage a kind of hermeneutical flexibility, where cultural relevance takes priority over fidelity to the text. Take 1 Timothy 2:12, for example, which prohibits women from “teaching or exercising authority.” Some have redefined the word “authority” (translated from the Greek authentein) to mean something like “domineering,” rather than general leadership. This reinterpretation has allowed egalitarian practices to emerge within frameworks that still claim to be complementarian. Meanwhile, some theological movements, like postliberalism, have shifted away from treating Scripture as a source of propositional truth. Instead, they focus on Scripture as a narrative—a communal story that evolves along with the community that tells it. This approach allows doctrines, like gender roles, to be reshaped based on changing cultural or communal values, rather than being grounded in the fixed authority of biblical texts.

Once ambiguous terms become institutionalized, they often normalize theological drift. Consider the Southern Baptist Convention, where the acceptance of “soft complementarianism”—such as allowing women to teach in seminaries—illustrates how vague terminology can blur boundaries. Even widely accepted conservative terms like “biblical inerrancy” have, in some cases, been stretched to accommodate historical-critical methods, eroding distinctions between evangelical and liberal scholarship. Leaders like J.D. Greear have contributed to this dynamic by framing complementarianism as a “celebration” of gender differences rather than as a hierarchical mandate. While well-intentioned, this reframing often leaves room for progressive reinterpretations, as seen in churches that permit women to preach under certain conditions, despite claiming to uphold complementarian principles.

What all of this shows is that ambiguous theological language acts like a solvent. It dissolves traditional boundaries and makes it easier for cultural and intellectual shifts to take hold. This isn’t to say that ambiguity is inherently liberal—it’s not. But when theological terms lack precision, they often enable gradual redefinition, aligning theology more closely with Enlightenment values like autonomy and equality. As Carl Trueman warns, churches don’t typically lose their way through blatant heresy. Instead, they do so through slow, incremental capitulation to cultural pressures, all while using language that still sounds orthodox.

To resist this drift, clarity is essential—not just in terms of the words we use, but in rooting those words firmly in biblical authority. Without that foundation, the line between faithfully adapting to modern contexts and surrendering to cultural trends becomes dangerously thin.

Ray Brandon lives in Kalamazoo and serves with Every Ethne as Director of Church Planting for North America.