After arriving in Australia last month, I caught a cold or something and after several days lost my voice. I felt a familiar sense of calm relief and remembered a similar occurrence in Singapore.
At that time, I realized that since I couldn't speak, I couldn't say anything wrong! I couldn't say anything I would regret later. I was saved from committing any negative verbal karma. For once, it was guaranteed that I couldn't get myself into trouble. Amazing. What a relief!
I carried a pad with me to be able to communicate, and soon realized that it would be extremely difficult to have an argument with someone if you couldn't speak. Talking is easy and quickly done. Writing takes much more time! Blurting out angry words is instantaneous. Having to write them down, you will quickly conclude that an argument is just more trouble than it's worth. It would be much easier to smile and get along with the other person.
As another nun pointed out, losing one's voice was an extreme way of not committing verbal karmas and not all that practical as advice. Fortunately, we don't need to lose our voice to achieve the same result. We can just talk less—a lot less.
As I learned that day, most of the talking we think is necessary is, in reality, completely unnecessary.