From Shragi: A nice vort sent to me. Our sages have said "Wise ones, be zehirim with your words." On a simple level, this relates to the word "zehirut" (caution), but it also relates to the word "zohar" (radiance). This implies that one should "radiate light" and be perfectly clear when expressing an idea. We should try to make what we are saying clear and bright.