Rebbe Yisroel of Rizhin once explained the difference between the opinion of the Talmudic School of Shammai and the School of Hillel concerning lighting the Chanuka Menorah. The School of Shammai maintained that eight candles should be kindled on the first night, decreasing on each successive night until the last night, when only one is kindled. The School of Hillel was of the opinion that one candle should be kindled on the first night and one candle added each night, until on the final night eight candles are lit.

The path to repentance requires looking forward, not dwelling on the past….

These two opinions represent two distinct paths of divine service. The School of Shammai understood that the way to coming close to G‑d begins with regret and remorse over the past, and one may even require mortifications to achieve his atonement, as in the verse "Turn from evil and do good." (Psalms 34:15) One must turn from bad ways and repair any damage that he caused. When the process is finished, he can then begin to do mitzvot. This position is represented in the School of Shammai's opinion on kindling the Chanuka lights. One must continually endeavor to diminish his transgressions until he is free from evil - only then can he turn his full attention to doing more mitzvot.

The School of Hillel, on the other hand, held that one should immediately begin to repair one's ways by learning Torah and performing mitzvot. The positive path of learning and mitzvot automatically disassociates one from harmful actions. The path to repentance requires looking forward, not dwelling on the past. Replacing bad habits with goods ones is the proper divine service.

This is why the School of Hillel taught to add a candle each night, signifying that Torah learning and mitzvot add to one's life.

The Rebbe explained that this teaching is illustrated in the verse "And these are the laws that you must set before them." (Ex. 21:1) The term "before them" means that a person should take the "positive" path to repentance and self- improvement. The Rizhiner taught that concentrating on the positive, learning Torah and performing mitzvot is building for the future. The way of regret and remorse over past deeds is call "from behind".

[Adapted from Ner Yisrael, vol. 1, parashat Mishpatim by Rabbi Yisrael Friedman of Ruzhin
First published in B'Ohel Hatzadikim, Mishpatim 5760]