As we learned on yesterday’s daf, Rabbi Yehuda ben Betera forbids using paper that had been erased or using diftira for a geṭ, since writing on those items can be forged easily. The Hakhamim of the Mishna disagree, since – as the Gemara explains – they rely on the witnesses who attest to the validity of the document.
In an attempt to define the term diftira, our Gemara brings the opinion of Ulla, who is quoted by Rabbi Hiyya bar Ami as saying that there are three types of animal hides:
- Matzah – as its name implies, is bland. It has been neither salted nor treated with flour nor with gall-nut.
- Hiyfa – has been salted but not treated with flour or gall-nut.
- Diftira – has been salted and treated with flour but not with gall-nut.
There are many stages in the processing of raw hides into leather, and significant differences in the way the processing is done, depending on the intended final use of the animal skin. The three stages mentioned in our Gemara do not encompass all of the different parts of curing hides, and deal very specifically with the processing stages in preparing an animal skin to be used for writing.
After the hide is soaked, the remnants of the animal’s meat are removed and the initial processing is completed, it was common practice to soak the skin in salt (today it is soaked in other chemicals, as well). The next step is to put it into a flour and water mixture so that the leavening action of the flour mixed with water will help solidify the skin. The addition of tannins from processed gall-nuts, also called oak apples, is the final stage before the hide is ready to be used for writing.
Rashi points out that klaf – parchment – is not mentioned because it has reached a point in processing that it is considered a different entity, and not animal skin.