A Kosher phone. Kosher food. Kosher thoughts.
In Torah we – are careful what we ingest. Vegans & Vegetarians are careful because they don’t want to hurt animals. We eat Kosher – that is careful not to hurt animals – in the sense that animals are slaughtered without feeling pain. But in Kosher food – we also refrain from hurting our souls.
We do not eat non-kosher not because it is not healthy. Non kosher food may be very healthy. We do not eat it because we are concerned with our souls. Non-kosher food is detrimental to our souls. The Torah wants us to be refined. Eating an unrefined animal may cause us to acquire some of the unrefined characteristics of that animal.
When we have a wedding we make sure the food is Kosher for the guests. But more than that we are careful to not to cause things detrimental to the soul of others. In Torah-observant weddings there is music, dancing, food and holiness.
The bride and groom are entering into holy matrimony. One of the ways we keep this wedding holy is to separate the men and the women. We hold dancing separately as to not cause promiscuity and incite improper thoughts among the guests.
The sages say that having a separate-dancing wedding helps the couple. It brings holiness to the couple’s relationship. It prevents them from having problems later in life.
If you think of it it makes sense having separate dancing at a wedding & Bar Mitzvah. For the bar mitzvah – we celebrate the boy becoming a man – being responsible to observe the Mitzvot of Hash-m. Yes dance. But to dance mixed is to turn a meaningful event into a disco. That’s inappropriate. The same applies to the wedding. Why turn a holy event into a cheap discotheque?
Torah says that the departed relatives of the bride and the groom attend a kosher wedding. Let them enjoy the wedding.