The phrase "letting pass" means to ignore, disregard or overlook something. Some antonyms for letting pass are "confronting," "opposing," "challenging," "questioning," and "dissuading." These words are used to convey a sense of skepticism or disagreement with a particular idea or action. For instance, if someone is letting pass a bad idea, then confronting them may be the best course of action. In other words, go against their perspective instead of agreeing with it. When someone is letting pass something dangerous, opposing the approach or questioning the feasibility can prevent harmful situations. Therefore, it's essential to have antonyms for letting pass in our vocabulary to avoid being complacent and to challenge beliefs from time to time.