Lighting Shabbat Candles I
I have been teaching a course in which we are examining two different questions relating to the lighting of shabbat candles, whether a blessing is required and if the lighting of shabbat candles is considered kabbalat shabbat, i.e. if lighting shabbat candles initiates the accepting upon oneself of shabbat prohibitions. I won’t be going over all of the sources that we are covering in class, but will address most of the important ones.
Sources from the Mishnah and the Talmuds:
There are a number of sources in Tannaitic literature which take it as a given that candles are lit for shabbat.  See e.g. the second chapter of Mishnah Shabbat, esp. mishnahs 6-7. While it seems to have been accepted that shabbat candles were lit, there is NO source in either the Mishnah or the Talmuds which says that one must recite a blessing when shabbat candles are lit.  On Shabbat 25b lighting shabbat candles is designated as a חובה, a term whose definition is unclear, but there is no mention of any blessing. While there is no Talmudic source which mentions a blessing, a source which will become important later on is Pesachim 7b, which requires that all blessings be recited before the performance of the mitzvah with which they are associated, כל המצות מברך עליהן עובר לעשייתן.
It is also unclear from the Talmud whether lighting shabbat candles is kabbalat shabbat or not. There are two important sugyot which in my opinion suggest that lighting shabbat candles is not kabbalat shabbat, although their interpretation was disagreed upon by later commentators. On Shabbat 35b there is a discussion of the sequence of shofar blasts which heralded in the shabbat. It says that,
When the third blast was begun, what was to be removed was removed, and what was to be stored away was stored away, and the lamp was lit. Then there was an interval for as long as it takes to bake a small fish or to place a loaf in the oven; then a teki’ah, teru’ah and a teki’ah were sounded, and one commenced the Sabbath.
Later commentators disagreed about the meaning of the phrase “ושוהה כדי צליית דג קטן, או כדי להדביק פת בתנור” (“Then there was an interval for as long as it takes to bake a small fish or to place a loaf in the oven”), whether this was a description of what people were actually able to do after candles were lit, or if it was just a designation of a certain amount of time, similar to כדי אכילת פרס.
The other important Talmudic source is found on Berachot 27b.
Has not R. Abin related that once Rab said the Sabbath Tefillah on the eve of Sabbath and he went into the bath and came out and taught us our section, while it was not yet dark? — Raba said: He went in merely to perspire, and it was before the prohibition had been issued. But still, is this the rule? Did not Abaye allow R. Dimi b. Levai to fumigate some baskets? — In that case there was a mistake. But can [such] a mistake be rectified? Has not Abidan said: Once [on Sabbath] the sky became overcast with clouds and the congregation thought that is was night-time and they went into the synagogue and said the prayers for the termination of Sabbath, and then the clouds scattered and the sun came out and they came and asked Rabbi, and he said to them, Since they prayed, they have prayed? — A congregation is different, since we avoid troubling them [as far as possible].
This discussion is predicated on the belief that it is prayer which initiates the observance of shabbat, therefore any prohibited behavior after one prayed would be problematic.
Next: The Geonim.
 It is important to note that all of the Talmudic sources use the phrase נר שבת, the “shabbat candle” in the singular. It isn’t until the medieval period that there is a discussion of נרות שבת, shabbat candles. Despite this fact, because of common usage, שגרת לשון, I will write shabbat candles.
 There are a number of medieval sources which claim that in the Jerusalem Talmud there is a source which requires a blessing on shabbat candles, but we will see that there is no such source in the Jerusalem Talmud.