Hi Rabbi Simon
I have anther question. I have seen people light candles for various tzadikim. What are the rules regarding this? I would like to light for rebbe nachman, rebbe shlomo carlebach and my grandma.
Lighting a candle to mark the yahrtzeit (anniversary of the death, on the Hebrew calendar) of a relative, a tzaddik, or indeed any person is perfectly permissible. The time to light it would be at night, as the day of the yahrtzeit begins, customarily for 24 hours. It would be appropriate for the candle to be positioned in a safe place (obviously) and one where it can be observed, however not where you will need its light for reading, etc. I.e. it should be designated as a symbolic, not a utilitarian flame. Of course, nowadays this is very easy to achieve, as we primarily use electric lights for our needs.