Shared ground
Jesus takes a dispute about cleanliness and states a public principle: eating something does not make a person “unclean,” but what comes out of the mouth does (vv.10–11). The focus moves from external inputs to a person’s inner life showing itself outwardly.
The disciples then report that recognized teachers were “offended,” meaning they treated Jesus’ saying as unacceptable or dangerous (v.12). Jesus answers by judging the stability and trustworthiness of these leaders: what God did not originate will not last, and following “blind” guides ends in ruin (vv.13–14; blind).
Where interpretation differs
What “defile” means here. Some read “defile” mainly as ritual contamination (clean/unclean status). Others think Jesus is also making a moral claim: true impurity is ethical and heart-deep, not food-based.
What “what comes out of the mouth” includes. Some take it narrowly as speech itself (words that reveal the heart). Others take it more broadly as the inner person expressed outwardly—speech as the headline example, but not the only one.
What “every plant” refers to. Some think Jesus is primarily talking about teachings and leader-made rules; others think he is mainly talking about people/leaders themselves; some include both (leaders and what they are cultivating).
Why the disagreement exists
Jesus uses short, picture-like statements without spelling out the scope. The surrounding discussion in the chapter is about purity practices and inherited customs, which pushes some readers toward “ritual” meanings. But Jesus’ contrast between “in” (food) and “out” (speech) pushes others toward “heart/moral” meanings. Likewise, “plant” and “uprooted” can naturally point either to ideas (things planted in communities) or to the persons who promote them.
What this passage clearly contributes
- It explicitly shifts the center of “uncleanness” away from what is eaten and toward what a person expresses in speech (vv.10–11).
- It presents offense at Jesus’ teaching as a marker of a deeper conflict about authority and truth (v.12).
- It explicitly warns that some influential guides are unreliable (“blind guides”) and that following them leads to harm (v.14).
- It asserts that what does not come from the Father will ultimately be removed, even if it is presently established and defended by respected leaders (v.13).