When to recite the berachah for Shabbat candles

Hi,

In Friday's halachah I mentioned a blessing one recites "before lighting." The question of when one recites the blessing is actually subject to debate:

1. In general, one who is about to perform a mitzvah recites the blessing for the mitzvah before performing the mitzvah, and so one should recite the blessing before lighting;

2. Reciting this blessing might constitute accepting Shabbat, and therefore one could not recite the blessing and then light the candles!

Because of concern #2, the general practice is to light and then recite the blessing afterward. To mitigate concern #1, the lighter doesn't look at the candles until after reciting the blessing; this helps somewhat, because one has not benefited from the mitzvah until after the blessing.

(Code of Jewish Law Orach Chaim 263:5; Mishneh Berurah 263:26-27)

Have a great day,
Mordechai