What is the Purpose of the Haggadah?

The lighting of candles, or oil, plays a central role in Jewish life. Shabbat and festivals commence with the lighting of candles and Shabbat concludes with the lighting of a candle, we light candles to commemorate our loved ones, and we mark Chanukah with the lighting of candles in ascending order from the first to the eighth night. Since at least one of the eight days of Chanukah falls on Shabbat, and we have to, then, light two sets of candles, I would like to explain the difference between them and see what lessons we may learn that are relevant to our lives today.