MISHNA: If an alleyway is enclosed on three sides with courtyards opening into it from three sides, and the fourth side opens into a public domain, it is prohibited by rabbinic law to carry objects in it on Shabbat. However, carrying in an alleyway under those circumstances is permitted if a cross beam is placed horizontally over the entrance to the alleyway. The mishna teaches that if the cross beam spans the entrance to an alleyway at a height above twenty cubits, one must diminish the height of the cross beam so that it is less than twenty cubits. Rabbi Yehuda says: He need not diminish it, since the cross beam enables one to carry in the alleyway even at that height.

If the entrance to the alleyway is wider than ten cubits, one must diminish its width. However, if the entrance to the alleyway has the form of a doorway, i.e., two vertical posts on the two sides, and a horizontal beam spanning the space between them, even if it is wider than ten cubits, he need not diminish it, as it is then regarded as an entrance, rather than a breach, even if it is very wide.

GEMARA: We learned in a mishna there, in tractate Sukka: A sukka that is more than twenty cubits high is unfit, and Rabbi Yehuda deems it fit. The halakhot are similar in substance but differ in formulation, and accordingly the Gemara asks: What is the difference that with regard to a sukka the mishna teaches that it is unfit, whereas with regard to an alleyway, it teaches the method of rectification, that one must diminish the height of the cross beam?

The Gemara answers: With regard to sukka, since it is a mitzva by Torah law, the mishna teaches that it is unfit, as if it is not constructed in the proper manner, no mitzva is fulfilled. Whereas with regard to an alleyway, where the entire prohibition of carrying is only by rabbinic law, the mishna teaches the method of rectification, as the cross beam comes only to rectify a rabbinic prohibition, but does not involve a mitzva by Torah law.

The Gemara suggests an alternative explanation: And if you wish, say instead that even with regard to matters prohibited by Torah law, it would have been appropriate for the mishna to teach a method of rectification. However, with regard to sukka, whose matters are numerous, it categorically teaches that it is unfit. Merely diminishing the height of a sukka is insufficient to render it fit; it must also satisfy requirements governing its size, its walls, and its roofing. Teaching the remedy for each disqualification would have required lengthy elaboration. With regard to an alleyway, however, whose matters are not numerous, the mishna teaches the method of rectification. Once the height is diminished, it is permitted to carry in the alleyway.

Rav Yehuda said that Rav said: The Rabbis only derived this halakha, that an opening more than twenty cubits high is not considered an entrance, from the doorway of the Sanctuary, the inner sanctum of the Temple. And Rabbi Yehuda only derived his opinion, that even an opening more than twenty cubits high is considered an entrance, from the doorway of the Entrance Hall leading into the Sanctuary.

As we learned in a mishna: The doorway of the Sanctuary is twenty cubits high and ten cubits wide, and that of the Entrance Hall is forty cubits high and twenty cubits wide.

The Gemara explains the basis of this tannaitic dispute. Both of them, the Rabbis and Rabbi Yehuda, interpreted the same verse homiletically: ''And he shall lay his hand upon the head of his offering and slaughter it at the doorway of the Tent of Meeting, and Aaron’s sons, the priests, shall sprinkle the blood on the altar round about'' (Leviticus 3:2). As the Rabbis hold that the sanctity of the Sanctuary is discrete and the sanctity of the Entrance Hall is discrete, i.e., the Sanctuary and the Entrance Hall have distinct levels of sanctity. And since the essence of the Temple is the Sanctuary and not the Entrance Hall, and since the Sanctuary in the Temple parallels the Tent of Meeting in the Tabernacle, when the verse speaks of the doorway of the Tent of Meeting, it is referring to the doorway of the Sanctuary. Therefore, the term doorway applies to an opening similar to the doorway of the Sanctuary, which is twenty cubits high. There is no source indicating that an opening with larger dimensions is also considered a doorway.

And Rabbi Yehuda holds that the Sanctuary and the Entrance Hall are one, equal, sanctity, and therefore, when it is written: ''The doorway of the Tent of Meeting,'' it is referring to both of them, and accordingly, the term doorway applies to a larger entrance as well.

The Gemara suggests an alternative understanding of the dispute. And if you wish, say instead that even according to Rabbi Yehuda, the sanctity of the Sanctuary is discrete and the sanctity of the Entrance Hall is discrete. And here, this is the reasoning of Rabbi Yehuda: By fusing together language from different verses, the result is as it is written: To the doorway of the Entrance Hall of the House. Therefore, even the doorway of the Entrance Hall is referred to in the Torah as a doorway, and the same is true of any opening with comparable dimensions.

And the Rabbis say: Had the verse written: ''To the doorway of the Entrance Hall,'' it would be interpreted as you said. However, now that it is written: ''To the doorway of the Entrance Hall of the House,'' it is to be understood: To the doorway of the House that opens into the Entrance Hall, i.e., the Sanctuary, and consequently, the definition of doorway is derived from the dimensions of the doorway of the Sanctuary.

The Gemara raises a difficulty with the very basis of this explanation: But when this is written: ''The doorway of the Tent of Meeting,'' isn’t it written with regard to the Tabernacle in the wilderness? How can the status in the permanent Sanctuary, i.e., the Temple in Jerusalem, be derived from matters stated with regard to the Tabernacle?

The Gemara answers: We find that the Tabernacle is called Temple, and that the Temple is called Tabernacle; therefore, the halakhot that govern one can be derived from the other. As if you do not say so, that the Tabernacle and the Temple are one with regard to their halakhot, that which Rav Yehuda said that Shmuel said: Peace-offerings that were slaughtered in the Temple prior to the opening of the doors of the Sanctuary in the morning are disqualified would be difficult. That halakha is derived as it is stated: ''And he shall slaughter it at the doorway [petaḥ] of the Tent of Meeting,'' from which it is derived: When the doors to the Tent of Meeting are open [petuḥin], and not when they are closed. But when this is written: The doorway of the Tent of Meeting, isn’t it written with regard to the Tabernacle? Rather, for halakhic purposes, we find the Temple called Tabernacle, and the Tabernacle called Temple.

The Gemara questions its previous conclusion: Granted, the Temple is called Tabernacle, as it is written: ''And I will set My Tabernacle among you'' (Leviticus 26:11), and the reference is to the permanent Sanctuary, i.e., the Temple, as the verse is referring to that which will transpire after the Jewish people settle in their land. However, the fact that the Tabernacle is called Temple, from where do we derive it? The Gemara answers: If you say that it is derived from that which is written: ''And the Kehatites, the bearers of the Temple, set forward, that they may set up the Tabernacle before they came'' (Numbers 10:21),