Whereas last weeks word, leshon sagi nahor, referred to speaking in opposites as a type of euphemism, lashon nekiyah, clean language, is a form of speech that avoids all direct reference to anything deemed rude.

I was reminded of this term when collecting my two-and-a-half-year-old daughter from her nursery. In response to my question, Did you use the toilet today? I was told by her teacher that they called it the beit hakiseh, which literally means the house of the chair, lashon nekiyah for the toilet..

According to the Talmud, it was the mark of a worthy sage to speak in lashon nekiyah, and indeed Rav would not speak to those who did not choose their words carefully. As Rabbi Yehoshua ben Levi declared, One should never allow something disgraceful to escape from ones mouth.

The opposite of lashon nekiyah is nibul peh (obscene language) and is considered a transgression. The Maharal teaches that foul words do damage to our very humanity, for speech is one of the things that separate us from all other creatures.

Isaiah thought himself unworthy of prophecy, For I am a man of unclean lips and I live among a people of unclean lips (Isaiah 6:5). The words that we choose to describe our world spiritually impact on us and those around us.

Lashon nekiyah is not a way of denying the less attractive side of life but a decision to insist on spiritual cleanliness when facing any aspect of reality.