The Ninevites believed in God, since they hearkened to the preaching of the prophet sent to them by God, and humbled themselves before God with repentance. They proclaimed a fast, and put on sackcloth (penitential garments: see at Joe 1:13-14; 1Ki 21:27, etc.), “from their great one even to their small one,” i.e., both old and young, all without exception. Even the king, when the matter (had-dâbhâr) came to his knowledge, i.e., when he was informed of Jonah's coming, and of his threatening prediction, descended from his throne, laid aside his royal robe ('addereth, see at Jos 7:21), wrapt himself in a sackcloth, and sat down in ashes, as a sign of the deepest mourning (compare Job 2:8), and by a royal edict appointed a general fast for man and beast. וַיַּזְעֵק, he caused to be proclaimed. וַיֹּאמֶר, and said, viz., through his heralds. מִפַּעַם הם, ex decreto, by command of the king and his great men, i.e., his ministers (פַעַם = פְעֵם, Dan 3:10, Dan 3:29, a technical term for the edicts of the Assyrian and Babylonian kings). “Man and beast (viz., oxen and sheep) are to taste nothing; they are not to pasture (the cattle are not to be driven to the pasture), and are to drink no water.” אַל, for which we should expect לֹא, may be explained from the fact that the command is communicated directly. Moreover, man and beast are to be covered with mourning clothes, and cry to God bechozqâh, i.e., strongly, mightily, and to turn every one from his evil ways: so “will God perhaps (מִי יוֹדֵעַ) turn and repent (yâshūbh venicham, as in Joe 2:14), and desist from the fierceness of His anger (cf. Exo 32:12), that we perish not.” This verse (Jon 3:9) also belongs to the king's edict. The powerful impression made upon the Ninevites by Jonah's preaching, so that the whole city repented in sackcloth and ashes, is quite intelligible, if we simply bear in mind the great susceptibility of Oriental races to emotion, the awe of one Supreme Being which is peculiar to all the heathen religions of Asia, and the great esteem in which soothsaying and oracles were held in Assyria from the very earliest times (vid., Cicero, de divinat. i. 1); and if we also take into calculation the circumstance that the appearance of a foreigner, who, without any conceivable personal interest, and with the most fearless boldness, disclosed to the great royal city its godless ways, and announced its destruction within a very short period with the confidence so characteristic of the God-sent prophets, could not fail to make a powerful impression upon the minds of the people, which would be all the stronger if the report of the miraculous working of the prophets of Israel had penetrated to Nineveh. There is just as little to surprise us in the circumstance that the signs of mourning among the Ninevites resemble in most respects the forms of penitential mourning current among the Israelites, since these outward signs of mourning are for the most part the common human expressions of deep sorrow of heart, and are found in the same or similar forms among all the nations of antiquity (see the numerous proofs of this which are collected in Winer's Real-wörterbuch, art. Trauer; and in Herzog's Cyclopaedia). Ezekiel (Eze 26:16) depicts the mourning of the Tyrian princes over the ruin of their capital in just the same manner in which that of the king of Nineveh is described here in Jon 3:6, except that, instead of sackcloth, he mentions trembling as that with which they wrap themselves round. The garment of haircloth (saq) worn as mourning costume reaches as far back as the patriarchal age (cf. Gen 37:34; Job 16:15). Even the one feature which is peculiar to the mourning of Nineveh - namely, that the cattle also have to take part in the mourning - is attested by Herodotus (9:24) as an Asiatic custom.
(Note: Herodotus relates that the Persians, when mourning for their general, Masistios, who had fallen in the battle at Platea, shaved off the hair from their horses, and adds, “Thus did the barbarians, in their way, mourn for the deceased Masistios.” Plutarch relates the same thing (Aristid. 14 fin. Compare Brissonius, de regno Pers. princip. ii. p. 206; and Periz. ad Aeliani Var. hist. vii. 8). The objection made to this by Hitzig - namely, that the mourning of the cattle in our book is not analogous to the case recorded by Herodotus, because the former was an expression of repentance - has no force whatever, for the simple reason that in all nations the outward signs of penitential mourning are the same as those of mourning for the dead.)
This custom originated in the idea that there is a biotic rapport between man and the larger domestic animals, such as oxen, sheep, and goats, which are his living property. It is only to these animals that there is any reference here, and not to “horses, asses, and camels, which were decorated at other times with costly coverings,” as Marck, Rosenmüller, and others erroneously assume. Moreover, this was not done “with the intention of impelling the men to shed hotter tears through the lowing and groaning of the cattle” (Theodoret); or “to set before them as in a mirror, through the sufferings of the innocent brutes, their own great guilt” (Chald.); but it was a manifestation of the thought, that just as the animals which live with man are drawn into fellowship with his sin, so their sufferings might also help to appease the wrath of God. And although this thought might not be free from superstition, there lay at the foundation of it this deep truth, that the irrational creature is made subject to vanity on account of man's sins, and sighs along with man for liberation from the bondage of corruption (Rom 8:19.). We cannot therefore take the words “cry mightily unto God” as referring only to the men, as many commentators have done, in opposition to the context; but must regard “man and beast” as the subject of this clause also, since the thought that even the beasts cry to or call upon God in distress has its scriptural warrant in Joe 1:20.