Rabbi Yisrael Salanter, pioneer of the ethical movement known as Mussar, said there was a link between the two sidrot. They teach us to be careful of two things at once what goes into the mouth (kashrut) and what comes out of it (care with one’s speech). Just as the wrong food can contaminate one’s person, so the wrong word can contaminate one’s soul.
The tragedy of our age is that some people take no notice of either requirement. Those who do not bother with kashrut think the whole subject unimportant.
“What difference does it make where I buy my meat?” they ask; “If I mix milk and meat, will the heavens really fall upon me?”
Very nice, but how can you be so certain that kosher or not kosher, it really doesn’t make a difference?
The body is delicately structured, and the kosher diet may well be the healthier one. Not that physical health considerations are the main reason for kashrut; it is the character, personality and identity of a Jew that are promoted by keeping kosher.
“What difference does it make whether my words are tactful or not?” one also hears. Oifn lung, oifn tsung, goes the phrase - “I believe in being blunt and that’s the way I am!”
But the problem is that your words can hurt, and when they hurt other people they hurt you yourself too. The rabbis say that evil talk harms three people the one who is spoken about, the one who hears the comments, and the one who utters them.
Another piece of rabbinic advice is rather to remain silent than to risk saying something untoward. “If a word is worth a sela (an ancient coin), silence is worth two,” the sages added.
It does nothing for your dignity, integrity or reputation if you bad-mouth people or even only peddle gossip. There is more than enough nastiness floating through the air already; if you can’t say something nice and encouraging, it is better to hold your peace and not say your piece.