Chazal tell us a very strange story based on the last verse in this week’s Portion. The Torah relates all the laws concerning which animals are Kosher to eat and which are considered contaminated and may not be eaten. It ends by saying: לְהַבְדִּיל בֵּין הַטָּמֵא וּבֵין הַטָּהֹר, “…to distinguish between the contaminated and the pure…”.(Lev. 11,47) This implies that the animals permitted are ‘pure’ and the ones forbidden are ‘contaminated’.
Chazal tells us the following story. Two students were sitting before the great sage Hillel. One asked, “Why must we harvest grapes while we are spiritually pure (טהור), yet need not gather olives while spiritually pure?” The other asked, “Why must we gather grapes while spiritually pure (טהור) yet we may gather olives while we are spiritually defiled (טמא)?” Hillel then remarked, “I am certain that this one (the first one) will be a great teacher in Israel.” (He was Rabbi Yochanan, who ended up as a great scholar among the Talmudic Rabbis.) What impressed Hillel was that the first one used positive language while the second one used negative language.
The Gemorrah is trying to impress upon us to always have a positive outlook and use positive language when we speak. This advice is not only for our speech but also in our general outlook. Speech is only a clue to our overall attitude.