hard

Distinctions

Kashah (קשה)

Both senses at once, physical rigidity and difficulty; it is the word for the "hard" work of Mitzrayim at Shemos 1:14 and 6:9.

• Shemos 7:3, that Hashem will harden (akasheh) Pharaoh's heart, is read by most commentators in the first sense, Pharaoh empowered to go on refusing and left unbudged by the makkos.
• Rabbi Yaakov Tzvi Mecklenburg prefers the second: Hashem conveyed to Moshe that He would put Pharaoh through a particularly traumatic ordeal, hard for his heart to endure.
• Rav Hirsch, on the interchange of kuf with yud and with gimmel, links kashah to yesh, existence, since to us the more solid a thing is the more real it seems, and to gishah/gashash, approaching and impacting, since only what is solid is felt to make contact. Rabbi Klein applies this to the Menorah of mikshah (Shemos 25:31, 37:22, Bamidbar 8:4), beaten out of a single block, which Rashi (to Shemos 25:31) says was hammered into shape: harder than cast metal, and made by the kind of impact Rav Hirsch describes.
• Rabbi Shlomo Pappenheim derives from the two-letter core ק-ש a family of hard things: kash, the stiff lower part of the stalk not even fit for fodder; kishu, the gourd with its hard rind; keshes, the unbending part of the archer's weapon; and mokesh, a trap made of something hard rather than a pliant net, and hard to escape.

In the language of Chazal, hekesh is the derashah that compares two areas of halachah juxtaposed in one pasuk, that is, the impact or collision of two realms in a single verse. The Arabic term qiyas names the process in Islamic law of deducing new rulings by analogy to existing ones, and in medieval Hebrew, under the influence of the Ibn Tibbon family who translated Judeo-Arabic works into Hebrew, hekesh took on that meaning too and came to mean any deductive analogy or syllogism. A kushya is a logical difficulty, the clash between a statement and what reason would say, and by a tradition from the Geonim leaving a matter as kashya does not mean the position is refuted, only that the difficulty stands and more study is needed. A kushya is not a she'eilah: the first tries to undo an assertion, the second only asks for information.

Kashiach (קשיח)

Twice in Tanach: the ostrich and stork, which lay eggs and may then callously abandon them to be trampled, the mother bird who "hardens herself against her young as though they were not hers" (Iyov 39:16); and Yeshayahu 63:17, why do You harden our hearts from fearing You.

• Ibn Ezra (to Iyov 39:16) and Radak (Sefer HaShorashim) define it as cruelty.
• Rabbi Shlomo Ibn Melech (Michlal Yofi to Yeshayahu 63:17) adds that it specifically denotes cruelty in the form of estrangement from one whom a person would otherwise have been expected to love. That approach supports the notion that the word does not share a grammatical root with kashah.
• Metzudas Tzion (to Yeshayahu 63:17 and Iyov 39:16) does connect them, reading kashiach as a portmanteau of kashah and sach, remove: one is harsh with another and then coldheartedly removes the harshness from his own thoughts, as in hesech hada'as, as though nothing out of the ordinary had happened.
• Rabbi Shlomo Pappenheim's list leaves kashiach out, since a third radical ches does not fit his system, which admits only hei, aleph, mem, nun, tav, yud, or vav as the added letter.

(In Modern Hebrew disk kashiach is a calque on the English "hard drive," rendering "hard" by kashiach, which of course has nothing to do with cruelty or estrangement.)

Perech (פרך)

Literally to break. A lung so dry that it is brittle is nifreches and the animal is treifah (Chullin 46b); a lulav dry enough to be brittle is likewise nifreches and pasul (Tosafos to Sukkah 29b); a pircha in the give and take of the Gemara is the question that breaks a chain of reasoning.

• Rashi (to Shemos 1:13): avodas parech is back-breaking labor.
• Rav Hirsch (to Shemos 1:13 and 26:31) takes the breaking as separating: the Egyptians drafted Yisrael as laborers in order to break the homogeneity of Egyptian society and create a class difference between themselves and the Jews, and he ties perech to paroches, the curtain separating the Kodesh from the Kodesh HaKodashim.
• A second line reads perech as uselessness, what crumbles to waste and serves no purpose: Toras Kohanim (to Vayikra 25:43) defines the forbidden perech labor as work with no limit or work that is needless, and Rabbi Saadia Gaon explains avodas parech as the pointless labor Egypt imposed.
• Rabbi Shlomo Pappenheim joins the two: the core sense is breaking a routine by interrupting it to begin again. The paroches announces that up to here is holy and from here on holier. Perech labor is the unfair practice of pulling a worker off one job to start another, so that he never has the satisfaction of finishing and feels all his work crumbling to nothing. That is what the Torah forbids with a Jewish bondsman and what Mitzrayim did to Yisrael.

The Haggadah defines avodah kashah as perech, and Onkelos (to Shemos 1:13-14, Vayikra 25:53) renders perech with the Aramaic cognate of kashah, kashyu. Rabbi Klein takes this to suggest that the two terms are more or less equivalent.

Sources

Rabbi Reuven Chaim Klein, "Shemot: Hard Work and Hard Hearts," What's in a Word?, Ohr Somayach, 9 January 2021.

Cited in the essay: Shemos 1:13-14, 6:9, 7:3, 25:31 with Rashi, 26:31, 37:22; Bamidbar 8:4; Vayikra 25:43 with Toras Kohanim, 25:53; Iyov 39:16 with Ibn Ezra; Yeshayahu 63:17 with Michlal Yofi and Metzudas Tzion; Chullin 46b; Tosafos to Sukkah 29b; Targum Onkelos to Shemos 1:13-14 and Vayikra 25:53; Radak, Sefer HaShorashim; Ohel Moed of Rabbi Shlomo of Urbino; Rabbi Yaakov Tzvi Mecklenburg, HaKsav VeHaKabbalah.