Trying to understand the מכות, the plagues, in a broader context within Tanach presents a formidable, if not insurmountable challenge. While it might be conceivable to compare ארבה, the plague of locusts, for example, to a similar event described in ספר יואל, what parallel could one even imagine for a plague like צפרדע, the frogs? Moreover, various Midrashim attempt to see some kind of internal structure within the מכות, such as that hinted at, according to many commentaries on the Haggadah, by Rabbi Yehudah's famous acronym of דצ"ך עד"ש באח"ב, mentioned at the Seder on Pesach. This makes comprehending the מכות all the more difficult.
One מכה in particular, though, stands out even more than the others. Whereas the arrival of any of the מכות is nothing less than miraculous, this one's very existence appears impossible. This plague is, of course, the plague of ברד, which the Torah describes as hailstones with a core of fire (שמות ט:כ"ד). According to the laws of science, either the fire should melt the hail or the liquid in the hailstones should extinguish the fire; their coexistence is thus incomprehensible.
Interestingly enough, however, at least according to one opinion in the Midrash, this enigma might actually have a parallel in creation itself. In trying to understand the origin of the word "שמים" (heavens), an anonymous Tanna (cited by Rashi in his comment on בראשית א:א) suggests that it is a contraction of the two words אש, fire, and מים, water; the heavens thus consist of these two elements. In other words, the very existence of the heavens is in fact predicated on the notion that two mutually exclusive ideas actually can, and indeed must coexist, without either of them compromising the essence of the other.
One may suggest that this is the thought behind the request which concludes our every Tefillah. We say עושה שלום במרומיו הוא יעשה שלום עלינו, may He who makes peace on high make peace among us. In the heavens, there are two elements which are mutually incompatible by definition, yet somehow Hashem makes peace between them, allowing them each to continue their uncompromised existence. Neither is sacrificed for the benefit of the other, and without either one, the שמים could not be sustained. We thus pray that just as Hashem maintains the delicate balance in heaven, He grant us the wisdom and strength to learn how to live and thrive here on earth alongside those whom we find to be antithetical to our very beings.