My weekly email from Rebbetzin Chana Bracha Siegelbaum provided these perfect words for us all on Shabbos this week -
"The candle, which symbolizes the words of Torah, is considered a guide to life, safeguarding us from stumbling.
Whoever performs a mitzvah sustains his soul, and is considered as if he lit a candle before G-d as it states:
Ner Hashem nishmat adam
A candle of G-d is the soul of man.
The benefit of the candle is that it purifies the soul.
Candles differ from other goods in this world, which becomes reduced when shared with others. From one candle you can kindle thousands of candles without diminishing the light of the original candle.
In the same way, when we fulfill a mitzvah even if it seemingly comprises expense and effort, we do not get depleted but rather recharged with renewed spiritual energy."