but its general law can be learnt from it: then it is correct. But if we hold that neither can it be learnt from the general proposition, nor can the general proposition be learnt from it, then this [law] is required for its own purpose? — Since [Scripture] restored it, it restored it. Mar Zutra son of R. Mari said to Rabina: Yet say, When Scripture restored it [to the general proposition] [it was only] in respect of the presentation of the blood and emmurim, since this requires priesthood; but slaughtering, which does not require priesthood, does not require the north [either]? — If so, let Scripture say, ‘for it is as the sin-offering’: why [state], ‘for as the sin-offering so is the guilt-offering’? [To teach:] Let it be like the other guilt-offerings. Why must it be likened to both a sin-offering and a guilt-offering? — Said Rabina, It is necessary: if it were likened to a sin-offering and were not likened to a guilt-offering I would say, Whence did we learn [that] a sin-offering [is slaughtered in the north]? from a burnt-offering: thus that which is learnt through a hekkesh in turn teaches through a hekkesh. Mar Zutra the son of R. Mari said to Rabina: Then let it be likened to a burnt-offering and not likened to a sin-offering? — Then I would say, [that elsewhere] that which is learnt through a hekkesh in turn teaches through a hekkesh; and if you object, Then let it be likened to a sin-offering, [I could reply:] It [Scripture] prefers to liken it to the principal rather than to the secondary. Therefore it likened it to a sin-offering and it likened it to a burnt-offering, thus intimating that that which is learnt through a hekkesh does not in turn teach through a hekkesh. Raba said: [It is learnt] from the following, for it is written, As is taken off from the ox of the sacrifice of peace-offerings. For what purpose [is this written]? if for the lobe of the liver and the two kidneys, [surely] that is written in the body of the text! But because [Scripture] wishes to intimate that [the burning of] the lobe of the liver and the two kidneys of the he-goats [brought as sin-offerings] for idolatry shall be learnt by analogy from the community's bullock [for a sin-offering on account] of [sinning in] unawareness, whereas this law is not explicitly stated in the passage on the bullock of unawareness, but is learnt from the anointed priest's bullock: therefore ‘as is taken off’ is required, so that it might count as written in that very passage and not as something which is learnt through a hekkesh and then in turn teaches through a hekkesh. Said R. Papa to Raba: Then let [Scripture] write it in its own context, and not assimilate [it to the anointed priest's bullock]? — If [Scripture] wrote it in its own context, and did not teach it by assimilation, I would say, That which is learnt through a hekkesh can in turn teach through a hekkesh; and if you object, Then let Scripture assimilate it? [I could answer that Scripture] prefers to write it [explicitly] in its own context rather than to teach it through a hekkesh. Therefore [Scripture] wrote it and assimilated it, in order to teach that that which is learnt through a hekkesh does not in turn teach through a hekkesh. (Mnemonic: Hekkesh and gezerah shawah; kal wa-homer.) [It is agreed that] that which is learnt through a hekkesh does not in turn teach through a hekkesh, [this being learnt] either by Raba's or by Rabina's [exegesis]. Can that which is learnt through a hekkesh teach through a gezerah shawah? — Come and hear: R. Nathan b. Abtolemos said: Whence do we know that a spreading outbreak [of leprosy] in garments [covering the whole] is clean? Karahath [baldness of the back of the head] and gabbahath [baldness of the front] are mentioned in connection with garments, and also in connection with man: just as in the latter, if [the plague] spread over the whole skin, he is clean; so in the former too, if it spread over the whole [garment], it is clean. And how do we know it there? Because it is written, [And if the leprosy . . . cover all the skin . . .] from his head even to his feet, and [thereby] his head is assimilated [through a hekkesh] to his feet: as there, when it is all turned white, having broken out all over him, he is clean; so here too, when it breaks out all over him, he is clean. Said R. Johanan: In the whole Torah we rule that whatever is learnt can teach, save in the case of sacrifices, where we do not rule that whatever is learnt can teach. For if it were so [that we did rule thus], let ‘northward’ not be said in connection with a guilt-offering, and it could be inferred from sin-offerings by the gezerah shawah of ‘it is most holy’. Surely then its purpose is to teach that that which is learnt by a hekkesh does not in turn teach through a gezerah shawah. But perhaps [we do not learn it there] because one can refute it: as for a sin-offering, [it requires north] because it makes atonement for those who are liable to kareth? — A superfluous ‘most holy’ is written. That which is learnt through a hekkesh teaches in turn by a kal wa-homer. 40ᵃᵇᶜᵈᵉᶠᵍʰⁱʲᵏˡᵐⁿᵒᵖᵠʳˢᵗᵘᵛʷˣʸᶻᵃᵃᵃᵇᵃᶜᵃᵈᵃᵉᵃᶠᵃᵍᵃʰᵃⁱᵃʲᵃᵏᵃˡᵃᵐᵃⁿ