Many Torah commentators relating to the episode of Keri’at Yam Suf (the splitting of the Reed Sea) overlook a simple, yet significant question: why do Hazal, the Jewish Sages, refer to the miracle as a keri’ah – tearing – whereas the Torah describes it as a beki’ah, splitting? God instructed Moshe, “Netei et yadekha al ha-yam u-vka’eihu – Stretch forth your hand over the sea and split it,” and when Moshe did so, “va-yevake’u ha-mayim – the waters were split.” Later intra-Biblical references to the miracle also employ the term beki’ah. Not once in Tanakh does the term keri’ah appear in relation to water. Why, then, did Hazal deviate from the Torah’s terminology and choose to refer to this incident as Keri’at Yam Suf?
Credit for this question goes to R. Shmuel of Sieniawa. In his work Ramatayim Tzofim, R. Shmuel relates that he posed the above question to R. Yitzhak Meir Alter (1799-1866), the author of Hiddushei Ha-Rim. R. Alter explained that in order to understand why Hazal used the term keri’ah, we must turn to another context in which the term appears: Shabbat. One of the 39 melakhot is kore’a, tearing. According to R. Alter, the essence of kore’a sheds light on Keri’at Yam Suf because they share the same conceptual underpinnings; in other words, the halakhic definition of kore’a is the same process that occurred during Keri’at Yam Suf. How so?
R. Alter invoked a fundamental principle regarding kore’a. The Tosefta states, “[On Shabbat] one may tear the hide on top of a barrel of wine or brine provided that he does not intend to create a spout.” This ruling is difficult to understand; why is there no prohibition of kore’a here? To explain the Tosefta, R. Shneur Zalman of Liadi (1745-1812) suggested that the definition of kore’a is tearing apart two entities attached by artificial means – for example, sewing or gluing – whereas tearing apart material that is naturally one piece does not constitute kore’a. Thus, in our case, since the hide is a single entity, one may tear it on Shabbat.
Similarly, Rambam states that disconnecting the outer layer of a hide from its inner layer violates the melakhah of mafshit – skinning – yet elsewhere he states that tearing apart hides that were artificially glued together violates the melakhah of kore’a. In order to explain the distinction between these two cases, R. Avraham Danzig (1748-1820) reached the same conclusion: the latter case involves separate hides artificially glued together, and thus tearing them apart constitutes kore’a; in the former case, however, the hide is naturally one entity, and thus does not pose a problem in terms of kore’a.
What is the logic behind this distinction? The Mishnah presents the melakhah of kore’a in contradistinction to the melakhah of tofer, sewing; thus, it is reasonable to suggest that whereas the latter is the joining of two entities through a third medium, the former is the separation of those two entities through tearing.
Now let us return to our initial question: why did Hazal call the miracle Keri’at Yam Suf? To complete his answer, R. Alter cited a midrash in which R. Yohanan states that God created the Yam Suf on condition that it would be “torn” before the Jewish nation at the necessary moment. On the basis of the halakhic discussion above, as well as this Midrash, R. Alter suggested that God created the Yam Suf by fusing together two seas such that when the Jews would need to cross, the two seas would literally be “torn” apart. Although the true nature of the phenomenon was invisible to onlookers, Hazal knew that in reality a keri’ah had occurred; thus, to hint at this deeper understanding, they called the miracle Keri’at Yam Suf. 
R. Shmuel identified another connection between Keri’at Yam Suf and the melakhah of kore’a. There is a general rule regarding all 39 melakhot that only acts which constitute tikun – improvement – qualify as melakhah, whereas acts which constitute mekalkel – destructive action – do not qualified as melakhah. Although kore’a is seemingly destructive, the Mishnah states that kore’a must be al menat litpor – tearing in order to sew. In other words, kore’a is constructive because it is necessary for the sewing process; otherwise, it would be only mekalkel. So too, suggested R. Shmuel, Keri’at Yam Suf was al menat litpor, because God subsequently restored the sea to its original state. R. Shmuel concluded that the miracle “was a real tikun and not in the category of mekalkel,” adding a philosophical rational: “God forbid that the miracle would occur as a result of a destruction of Creation.” In other words, since God created a perfect world, it is inconceivable that He would perform a destructive act on His creation; thus, it was imperative that the miracle be constructive.
However, it is difficult to understand this notion of tikun. To simply tear apart two pieces of cloth and subsequently re-sew them – without any improvement in the process – certainly does not constitute tikun. Similarly, if Keri’at Yam Suf was al menat litpor, then in what sense did God “improve” the Yam Suf? The sea remained exactly as it had always been! In order to fully understand the connection between Keri’at Yam Suf and the melakhah of kore’a, one must delve deeper into the nature of the requirement of al menat litpor. Why must kore’a be al menat litpor in order to constitute a melakhah on Shabbat?
One opinion views the requirement as preempting the issue of mekalkel, requiring a constructive purpose in an otherwise destructive act. Others, however, maintain that al menat litpor is modeled after the Mishkan, where the purpose of tearing was to re-sew the curtains of the Mishkan. According to the latter understanding, kore’a is only prohibited for the purpose of re-sewing, whereas any other constructive purpose would not pose a problem in terms of kore’a. However, there is a serious difficulty with the latter opinion. The Mishna states that it is prohibited on Shabbat to tear clothing out of anger or as an expression of avelut, even though there is no intention to re-sew the clothing. In both of these cases, the tearing is not al menat litpor, so why is it prohibited?
R. Eliyahu Mishkovsky suggests that usually kore’a functions merely as a means to an end. In other words, the goal is not the tearing per se, but rather the result thereof. Regarding such cases, Hazal had a tradition that the purpose must be specifically al menat litpor, following the model of the Mishkan (Tabernacle). However, when the tearing is an end in itself – that is, the goal is the tearing per se – there is no requirement of al menat litpor. In these instances, the act of tearing itself constitutes a bona fide kore’a. Thus, the Mishna prohibits tearing clothing to alleviate anger or to express aveilut (mourning), seeing as the goal is accomplished through the tearing itself rather than the result thereof.
Now we can understand the tikun of Keri’at Yam Suf. God did not tear the sea in order to improve it; rather, the act of tearing per se achieved several valuable functions. The Torah states that the miracle terrified the enemies of the Jews: “The nations heard; they trembled… Terror and dread will descend upon them; through the might of your arm they will be still as stone.” This concept parallels the Gemara’s case regarding one who tears clothing in order to intimidate others, which qualifies as kore’a. Additionally, the stated purpose of Keri’at Yam Suf was that the Egyptians would ultimately realize the one true god: “Mitzrayim will know that I am God.” Accordingly, Keri’at Yam Suf demonstrated God’s dominion over the laws of nature. Finally, Keri’at Yam Suf increased the Jews’ emunah, faith, in God: “Israel saw the great power that God had used against the Egyptians; the nation feared God; they had faith in God and in His servant Moshe.” Now we can fully appreciate the depth of Hazal’s terminology in deliberately choosing to characterize the miracle of the splitting of the Reed Sea as Keri’at Yam Suf.
 See e.g. Sotah 2a; Sanhedrin 22a.
 Exodus 14:16, 21.
 See e.g. Psalms 78:13; Isaiah 63:12; Nehemiah 9:11; cf. Psalms 136:15, which uses the term gozeir, “cutting.”
 An av beit din, head judge of a rabbinical court, in late 19th-century Europe.
 A commentary on the midrashic collection Tanna De-vei Eliyahu.
 Shabbat 73a.
 Ramatayim Tzofim to Tanna De-vei Eliyahu, Eliyahu Zutta 16:10. The chapter heading demarcates the section toward the teachings of R. Alter.
 Tosefta Shabbat 17:9, cited in Beit Yosef, Orah Hayim 314 and Magen Avraham ad. loc. 314:14.
 See Rambam, Mishneh Torah, Hilkhot Shabbat 10:11, who equates gluing with sewing regarding the melakhah of tofeir.
 Shulhan Arukh Ha-Rav, Orah Hayim 340:17.
 Rambam, Mishneh Torah, Hilkhot Shabbat 10:11, 11:6.
 Hayyei Adam, Hilkhot Shabbat 29:5:2.
 Shabbat 73a.
 Bereishit Rabbah 5:5.
 On this Midrash, see Maharal, Derekh Hayyim, Avot 5:6. On why the Torah used the term beki’ah, see further in Ramatayim Tzofim to Tanna De-vei Eliyahu, Eliyahu Zutta 16:10.
 Shabbat 105b. However, they are rabbinically prohibited.
 Shabbat 73a. The same holds true for other seemingly destructive melakhot; for example, moheik, erasing, is al menat li-khtov, in order to write.
 Ramatayim Tzofim to Tanna De-vei Eliyahu, Eliyahu Zutta 16:10.
 Cf. Maharal, Derekh Hayyim to Avot 5:6.
 See Tosafot to Shabbat 94a s.v. rebbe; Shulhan Arukh Ha-Rav, Orah Hayim 313:17.
 See Bei’ur Halakhah 340:14.
 This view is implicit in Rashi to Shabbat 48a s.v. hayiv hatat; Tosafot to Shabbat 73b s.v. ve-tzarikh le-eitzim; Ramban and Ritva to Makkot 3a.
 Shabbat 105b. In fact, the laws of aveilut prohibit re-sewing the torn clothing.
 This question was asked by Rav Akiva Eiger, gloss to Shabbat 73b; Hayyei Adam, Hilkhot Shabbat 29:1-2; Pri Megadim, Orah Hayim 340 (Mishbetzot Zahav 6 and Eishel Avraham 18).
 Cited in Noam Eliezer (Orah Hayim vol. 1), Ateret Yisrael 10:1 (pp. 323-324).
 Exodus 15:14-16.
 See Shabbat 105b.
 Exodus 14:4, 14:18.
 Ibid. 14:31.