A Spiritual Reason for Good Hygiene?

Growing up I always felt that good hygiene was beneath me. Who cares whether my hair is dirty or my room is messy? What does it matter in the grand scheme of things? It's what's inside that's important. I don't subscribe to these views quite as strongly any more, and the following paragraph says a little bit about why.

We heard ten or twenty minutes of teachings by the Dalai Lama at our center today, seeking to explain how karma works. Part of it was quite similar to Thich Nhat Hanh's closing paragraphs in a previous post. Namely, we should avoid actions that are likely to produce suffering for ourselves or others in the future. An interesting example regards hygiene. Killing another being produces bad karma, and this includes killing insects. So if you are faced with an insect infestation you incur quite a bit of negative karma by killing them. If you are faced with such a situation, you may be forced to kill the insects, despite the karmic consequences. For example, if they pose a health and happiness issue for yourself or others. The best way to avoid the karmic issue is to maintain good hygiene in the first place to stop the infestation from happening. Thus good hygiene becomes a spiritual principle whereby we avoid killing living creatures. Also, as humans with the divine spark, we need to be proud of ourselves, and making our surroundings more beautiful is part of that. It is paying homage to our wonderful nature and the blessings of our remarkable human birth.

Something else the Dalai Lama said really stuck out to me. He said we should never talk negatively about another person. That's pretty wild. I do know that in my case negative talk about others is usually an outward sign of my inner negativity, and doesn't have much to do with the object of criticism. Pondering it now, though, it seems like when there is gross injustice, or even minor injustice, for that matter, talking negatively about the perpetrators may be necessary in order to stop the injustice. Probably he means that we should never talk about others with malice-borne motives. Describing the negative situation in an effort to help others, sounds to me like a different kettle of fish, or however the saying goes.