This saying again emphasizes the importance of teaching. Christ knows that what He has just said was deeply opposed to the common religious thinking of the time. For that reason He urges people to listen not superficially, but to understand with depth. “Having ears” here means having a heart that is ready to receive and submit to the truth. This warning is always necessary when the matter concerns a person’s inner condition, because a person easily turns aside to outward issues and avoids the judgment of the heart.