Commentary for Shabbat 2:4
לֹא יִקֹּב אָדָם שְׁפוֹפֶרֶת שֶׁל בֵּיצָה וִימַלְאֶנָּה שֶׁמֶן וְיִתְּנֶנָּה עַל פִּי הַנֵּר בִּשְׁבִיל שֶׁתְּהֵא מְנַטֶּפֶת, אֲפִלּוּ הִיא שֶׁל חֶרֶס. וְרַבִּי יְהוּדָה מַתִּיר. אֲבָל אִם חִבְּרָהּ הַיּוֹצֵר מִתְּחִלָּה, מֻתָּר, מִפְּנֵי שֶׁהוּא כְלִי אֶחָד. לֹא יְמַלֵּא אָדָם אֶת הַקְּעָרָה שֶׁמֶן וְיִתְּנֶנָּה בְצַד הַנֵּר וְיִתֵּן רֹאשׁ הַפְּתִילָה בְתוֹכָהּ, בִּשְׁבִיל שֶׁתְּהֵא שׁוֹאֶבֶת. וְרַבִּי יְהוּדָה מַתִּיר:
One may not perforate the shell of an egg [the harder upper shell containing the egg] and fill it with oil and place it at the mouth of the lamp so that it drip [drop by drop into the lamp — a decree lest he take (oil) from it (on the Sabbath). And since he set it aside for the lamp, he would be liable by reason of "extinguishing."], even if it (the oil container) were earthenware [(to use) which is repulsive, still, they decreed thus. For since the burning wick is not in the vessel containing the oil, he might come to take (oil) from it, thinking that "extinguishing" does not obtain in such an instance.] And R. Yehudah permits it, [not decreeing that he might come to take from it; for he sees the oil dripping on the wick beneath.] But if the potter joined it first, it is permitted, for it is (then) one vessel. [The same applies if the owner joined it together with lime or clay on Sabbath eve. There is no need to fear, for because of (the gravity of) Sabbath transgression, he separates himself from it.] One may not fill a dish with oil, place it beside the lamp, and put the (bottom) end of the wick in it, so that it draw [oil to the burning head of the wick.] R. Yehudah permits it. [The Mishnah apprises us of the difference between R. Yehudah and the rabbis (in all three instances): the shell of the egg, the earthenware (container), and the dish. For if it apprised us of the shell of the egg (alone), I might say it is only here that the rabbis forbade it, for since it is not repulsive, he might come to take from it. But earthenware, which is repulsive — perhaps he would concur with R. Yehudah. And if it apprised us of earthenware (alone), I might say it is only here that R. Yehudah permitted it, but in the instance of the egg shell, perhaps he would concur with the rabbis. And if it apprised us of both, I might say it is only in these instances that R. Yehudah permitted it, because the egg shell and the earthenware are in the space of the lamp, above it, nothing intervening, so that there is no need to decree lest he take from it, for he (instinctively) separates himself from it. But with the dish, where there is intervention, the dish being placed at the side of the lamp, so that it is not felt to be part of the lamp, perhaps he would concur that (in such an instance) there is (need for) a decree. And if we were apprised of the dish (alone), I might say that it is only here that the rabbis forbade it, but in the other two instances, perhaps they would concur with R. Yehudah. We must, therefore, be apprised (of all three instances). The halachah is in accordance with the sages.]