מסכת כלים

פרק כח משנה ו

מטלית שטליה על הקפה

A patch (that was tamei midras) that was attached to a basket (which is not susceptible to becoming tamei midras; the patch then looses its status as an independent object)

(the combination of the two items) imparts tumah to one item (i.e. it is regarded as something that has come into contact with something that was tamei midras, or a rishon l'tumah, and has the power to render food it touches tamei)

and invalidates one (that is, the food it comes into contact with it would, as a sheini l'tumah, invalidate any terumah that it in turn touches);

if it is removed from the basket,

the basket imparts tumah to one and invalidates one (that is to say, it remains a rishon),

and the patch is tahor;

if it was attached to a cloth

it imparts tumah to two and invalidates one (the combined item, which is of the same material as the patch, assumes the status of the patch, which as something tamei midras, an av hatumah, can make another item tamei for contacting it, that item as a rishon can in turn can render food it touches tamei, and that food, as a sheini, can invalidate terumah);

if it was separated from the cloth,

the imparts tumah to one and invalidates one (as its status as an av was solely for being one with the patch),

and the patch imparts tumah to two and invalidates one;

and similarly if one attached it to sackcloth

or to hide,

these are the words of Rabbi Meir;

and Rabbi Shimon rules they are tahor (as he deems a cloth patch attached to a different material, like leather, is akin to a patch attached to a basket);

Rabbi Yosi says

on hide it is tahor

on sackcloth it is tamei

as it is woven.

שלש על שלש שאמרו

The three by three (fingerbreadths) that was referred to (as the minimum size of cloth to be susceptible to tumah),

excludes the hem (that is to say, when sewn as a patch, the edges of the material would be folded over to create a smooth edge; this extra bit is not counted as part of the three square fingerbreadths),

these are the words of Rabbi Shimon;

and the Sages say

exactly three by three (including the extra bit required for the hem).

(If a patch) was attached to the clothing from one side (i.e. only one edge of the patch was sewn on),

it is not (considered to be) attached;

from two sides opposite each other,

it is (considered to be) attached;

if it was made like a gamma (the Greek letter a gamma resembles an upside-down "L")

Rabbi Akiva rules it is tamei (it is considered to be attached)

and the Sages rule it is tahor.

Rabbi Yehudah says,

by what are we speaking?

By a cloak.

but by a shirt,

(if attached by one side) from above, it is (considered to be) attached (as a shirt would not be worn upside-down, and so the patch would not fall open),

from below it is not (considered to be) attached.