Then Job arose - The phrase to arise, in the Scriptures is often used in the sense of beginning to do anything. It does not necessarily imply that the person had been previously sitting; see 2-Samuel 13:13.
And rent his mantle - The word here rendered "mantle" מעיל me‛ı̂yl means an upper or outer garment. The dress of Orientals consists principally of an under garment or tunic - not materially differing from the "shirt" with us - except that the sleeves are wider, and under this large and loose pantaloons. Niebuhr, Reisebescreib. 1. 157. Over these garments they often throw a full and flowing mantle or robe. This is made without sleeves; it reaches down to the ankles; and when they walk or exercise it is bound around the middle with a girdle or sash. When they labor it is usually laid aside. The robe here referred ire was worn sometimes by women, 2-Samuel 13:18; by men of birth and rank, and by kings, 1-Samuel 15:27; 1-Samuel 18:4; 1-Samuel 24:5, 1-Samuel 24:11; by priests, 1-Samuel 28:14, and especially by the high priest under the ephod, Exodus 28:31. See Braun de vest Sacerd. ii. 5. Schroeder de vest. muller.
Hebrew p. 267; Hartmann Ilcbraerin, iii. p. 512, and Thesau. Antiq. Sacra. by Ugolin, Tom. i. 509, iii. 74, iv. 504, viii. 90, 1000, xii. 788, xiii. 306; compare the notes at Matthew 5:40, and Niebuhr, as quoted above. The custom of rending the garment as an expression of grief prevailed not only among the Jews but also among the Greeks and Romans. Livy i. 13. Suetonius, in "Jul. Caes." 33. It prevailed also among the Persians. Curtius, B. x. c. 5, section 17. See Christian Boldich, in Thesau. Antiq. Sacra. Tom. xii. p. 145; also Tom. xiii. 551, 552, 560, xxx. 1105, 1112. In proof also that the custom prevailed among the Pagan, see Diod. Sic. Lib. i. p. 3, c. 3, respecting the Egyptians; Lib. xvii. respecting the Persians; Quin. Curt. iii. 11; Herod. Lib. iii. in Thalia, Lib. viii. in Urania, where he speaks of the Persians. So Plutarch in his life of Antony, speaking of the deep grief of Cleopatra, says, περίεῤῥηξατο τοῦς πέπλους επ ̓ αὐτῷ perierrēcato tous piplous ep' autō. Thus, Herodian, Lib. i.: καῖ ῥηξαμένη εσθῆτα kai rēcamenē esthēta. So Statius in Glaucum:
Tu mode fusus humi, lucem aversaris iniquam,
Nunc torvus pariter vestes, et pectora rumpis.
So Virgil:
Tune pins Aeneas humeris abscindere vestem,
Auxilioque vocare Deos, et tendere palmas.
Aeneid v. 685.
Demittunt mentes; it scissa veste Latinus,
Conjugis attonitus fatis, urbisque ruina,
Aeneid 12:609.
So Juvenal, Sat. x.:
ut primos edere planctus
Cassandra inciperet, scissaque Polyxena palla.
Numerous other quotations from the Classical writers, as well as from the Jewish writings, may be seen in Ugolin's Sacerdotium Hebraicum, cap. vi. Thesau. Antiq. Sacrar. Tom. xiii. p. 550ff.
And shaved his head - This was also a common mode of expressing great sorrow. Sometimes it was done by formally cutting off the hair of the head; sometimes by plucking it violently out by the roots, and sometimes also the beard was plucked out, or cut off. The idea seems to have been that mourners should divest themselves of that which was usually deemed most ornamental; compare Jeremiah 7:29; Isaiah 7:20. Lucian says that the Egyptians expressed their grief by cutting off their hair on the death of their god Apis, and the Syrians in the same manner at the death of Adonis. Olympiodorus remarks on this passage, that the people among whom long hair was regarded as an ornament, cut it off in times of mourning; but those who commonly wore short hair, suffered it on such occasions to grow long. See Rosenmuller, Morgenland, "in loc." A full description of the customs of the Hebrews in times of mourning, and particularly of the custom of plucking out the hair, may be seen in Martin Geier, de Hebraeorum Luctu, especially in chapter viii.
Thesau. Antiq. Sacra. xxxiil. p. 147ff. The meaning here is that Job was filled with excessive grief, and that he expressed that grief in the manner that was common in his day. Nature demands that there should be "some" external expression of sorrow; and religion does not forbid it. He pays a tribute to the nature with which God has endowed him who gives an appropriate expression to sorrow; he wars against that nature who attempts to remove from his countenance, conversation, dress, and dwelling, everything that is indicative of the sorrows of his soul in a time of calamity. Jesus wept at the grave of Lazarus; and religion is not designed to make the heart insensible or incapable of grief. Piety, like every kind of virtue, always increases the susceptibility of the soul to suffering. Philosophy and sin destroy sensibility; but religion deepens it. Philosophy does it on principle - for its great object is to render the heart dead to all sensibility; sin produces the same effect naturally. The drunkard, the licentious man, and the man of avarice, are incapable of being affected by the tender scenes of life. Guilt has paralyzed their feelings and rendered tthem dead. But religion allows people to feel, and then shows its power in sustaining the soul, and in imparting its consolations to the heart that is broken and sad. It comes to dry up the tears of the mourner, not to forbid those tears to flow; to pour the balm of consolation into the heart, not to teach the heart to be unfeeling.
And fell down upon the ground - So Joshua in a time of great calamity prostrated himself upon the earth and worshipped, Joshua 7:6. - The Orientals were then in the habit, as they are now, of prostrating themselves on the ground as an act of homage. Job seems to have done this partly as an expression of grief, and partly as an act of devotion - solemnly bowing before God in the time of his great trial.
And worshipped - Worshipped God. He resigned himself to his will. A pious man has nowhere else to go in trial; and he will desire to go nowhere else than to the God who has afflicted him.

Rent his mantle - Tearing the garments, shaving or pulling off the hair of the head, throwing dust or ashes on the head, and fitting on the ground, were acts by which immoderate grief was expressed. Job must have felt the bitterness of anguish when he was told that, in addition to the loss of all his property, he was deprived of his ten children by a violent death. Had he not felt this most poignantly, he would have been unworthy of the name of man.
Worshipped - Prostrated himself; lay all along upon the ground, with his face in the dust.

Then Job arose, and (a) rent his mantle, and shaved his head, and fell down upon the ground, and worshipped,
(a) Which came not from impatience, but declares that the children of God are not insensible like blocks, but that in their patience they feel affliction and grief of mind: yet they do not rebel against God as the wicked do.

Then Job arose,.... Either from table, being at dinner, as some think, in his own house; it being the time that his children were feasting in their eldest brother's house; or from the business in which he was employed, which he stopped on hearing this news; or from his seat, or chair of state in which he sat; or rather the phrase only signifies, that he at once, with strength of body, and rigour of mind, which were not lost, as often they are in such cases, went about the following things with great composure and sedateness. It is indeed generally observed, that there is an emphasis to be put on the word "then", which may be as well rendered "and", as if Job sat and heard very sedately, without any perturbation of mind, the loss of his substance; but when tidings were brought him of the death of his children, "then" he arose, as being greatly moved and distressed; but it should be observed till now there was no stop or intermission in the messengers, but before one had done speaking, another came and began to tell his story, and so there was no opportunity, as well as not the occasion, of arising and doing what follows; and which he did, not through the violence of his passion, or excess of grief, but as common and ordinary things, which were used to be done in that country for the loss of relations, and in token of mourning for them:
and rent his mantle; or "cloak" (k), as Mr. Broughton; but whether this was an outward garment, as each of these seem to be, if the same with ours, or an interior one, as some think, it is not very material to know; both were rent by Ezra upon a mournful occasion, Ezra 9:3, and it was usual to rend garments for deceased relations, or when they were thought to be so, see Genesis 37:29, though some think that this was on the account of the blasphemous thoughts the devil now suggested into his mind, being solicitous to gain his point, and work upon him to curse God; upon which he rent his garment to show his resentment and indignation at the thought of it, as the Jews used to rend their garments at hearing of blasphemy; but the first sense is best:
and shaved his beard; either he himself, or his servant by his orders; and which was done among the eastern nations as a sign of mourning, see Isaiah 15:2 and among the Greeks, as appears from Homer (l); nor was this contrary to the law in Deuteronomy 14:1, where another baldness, not of the head, but between the eyes, is forbidden for the dead; besides this was before that law was in being, and, had it been, Job was not bound by it, being not of the Israelitish nation: some, as Jarchi, Aben Ezra, and other Jewish writers, interpret this of his plucking or tearing off the hair of his head; but this neither agrees with the sense of the word here used, which has the signification of shearing or mowing, rather than of tearing or plucking, nor with the firmness and composure of Job's mind, who betrayed not any effeminacy or weakness; and though he showed a natural affection for the loss of his substance, and children, as a man, and did not affect a stoical apathy, and brutal insensibility, yet did not give any extraordinary vent to his passion: he behaved both like a man, and a religious man; he mourned for his dead, but not to excess; he sorrowed not as those without hope, and used the common tokens of it, and rites attending it; which shows that mourning for deceased relations, if done in moderation, is not unlawful, nor complying with the rites and customs of a country, in such cases, provided they are not sinful in themselves, nor contrary to the revealed and declared will of God:
and fell down upon the ground; in veneration of God, of his holiness and justice, and as sensible of his awful hand upon him, and as being humbled under it, and patiently submitting to it; he did not stand up, and curse God to his face, as Satan said he would, but fell upon his face to the ground; he did not curse his King and his God, and look upwards, see Isaiah 8:21 but prostrated himself to the earth in great humility before him; besides, this may be considered as a prayer gesture, since it follows:
and worshipped; that is, God, for who else should he worship? he worshipped him internally in the exercise of faith, hope, love, humility, patience, &c. and he worshipped him externally by praising him, and praying to him, expressing himself as in the next verse: afflictions, when sanctified, humble good men, cause them to lie low in the dust, and bring them near to God, to the throne of his grace, and instead of arraigning his providence, and finding fault with his dealings, they adore his majesty, and celebrate his perfections.
(k) "pallium suum", Pagninus, Montanus, Junius & Tremellius, Piscator, Schultens; "tunicam suam", Munster, Cocceius, Schmidt, Jo. Henric. Michaelis. (l) , &c. Odyss. 4. ver. 198. & Odyss. 24. ver. 46.

Job humbled himself under the hand of God. He reasons from the common state of human life, which he describes. We brought nothing of this world's goods into the world, but have them from others; and it is certain we can carry nothing out, but must leave them to others. Job, under all his losses, is but reduced to his first state. He is but where he must have been at last, and is only unclothed, or unloaded rather, a little sooner than he expected. If we put off our clothes before we go to bed, it is some inconvenience, but it may be the better borne when it is near bed-time. The same who gave hath taken away. See how Job looks above instruments, and keeps his eye upon the First Cause. Afflictions must not divert us from, but quicken us to religion. If in all our troubles we look to the Lord, he will support us. The Lord is righteous. All we have is from his gift; we have forfeited it by sin, and ought not to complain if he takes any part from us. Discontent and impatience charge God with folly. Against these Job carefully watched; and so must we, acknowledging that as God has done right, but we have done wickedly, so God has done wisely, but we have done very foolishly. And may the malice and power of Satan render that Saviour more precious to our souls, who came to destroy the works of the devil; who, for our salvation, suffered from that enemy far more than Job suffered, or we can think.

Job arose--not necessarily from sitting. Inward excitement is implied, and the beginning to do anything. He had heard the other messages calmly, but on hearing of the death of his children, then he arose; or, as EICHORN translates, he started up (2-Samuel 13:31). The rending of the mantle was the conventional mark of deep grief (Genesis 37:34). Orientals wear a tunic or shirt, and loose pantaloons; and over these a flowing mantle (especially great persons and women). Shaving the head was also usual in grief (Jeremiah 41:5; Micah 1:16).

The Conduct of Job:
20, 21 Then Job arose, and rent his mantle, and shaved his head, and fell down upon the ground, and worshipped, and said, Naked came I out of my mother's womb, and naked shall I return thither: Jehovah gave, and Jehovah hath taken away; blessed be the name of Jehovah.
The first three messengers Job has heard, sitting, and in silence; but at the news of the death of his children, brought by the fourth, he can no longer overcome his grief. The intensity of his feeling is indicated by rising up (cf. Jonah 3:6); his torn heart, by the rending of his mantle; the conscious loss of his dearest ones, by cutting off the hair of his head. He does not, however, act like one in despair, but, humbling himself under the mighty hand of God, falls to the ground and prostrates himself, i.e., worshipping God, so that his face touches the earth. השׁתּחוה, se prosternere, this is the gesture of adoration, προσκήνησις.
(Note: Vid., Hlemann's Abh. ber die biblische Gestaltung der Anbetung, in his Bibelstudien, Abth. 1 (1859).)
יצתי is defectively written, as Numbers 11:11; cf. infra, Job 32:18. The occurrence of שׁמּה here is remarkable, and may have given rise to the question of Nicodemus, John 3:4 : μὴ δύναται ἄνθρωπος εἰς τῆν κοιλίαν τῆς μητρὸς αὐτοῦ δεύτερον εἰσελθεῖν. The writer of Ecclesiastes (Ecclesiastes 5:14) has left out this difficult שׁמה. It means either being put back into a state of unconsciousness and seclusion from the light and turmoil of this world, similar to his former state in his mother's womb, which Hupfeld, in his Commentatio in quosdam Iobeidos locos, 1853, favours; or, since the idea of אמּי בּטן may be extended, return to the bosom of mother earth (Ew., Hirz., Schlottm., et al.), so that שׁמה is not so much retrospective as rather prospective with reference to the grave (Bttch.), which we prefer; for as the mother's bosom can be compared to the bosom of the earth (Psalm 139:15), because it is of the earth, and recalls the original forming of man from the earth, so the bosom of the earth is compared to the mother's, Sir. 40:1: ἀφ ̓ ἡμέρας ἐξόδου ἐκ γαστρὸς μητρὸς ἕως ἡμέρας ἐπιταφῆς εἰς μητέρα πάντων. The writer here intentionally makes Job call God יהוה. In the dialogue portion, the name יהוה occurs only once in the mouth of Job (Job 12:9); most frequently the speakers use אלוה and שׁדי. This use of the names of God corresponds to the early use of the same in the Pentateuch, according to which שׁדי is the proper name of God in the patriarchal days, and יהוה in the later days, to which they were preparatory. The traditional view, that Elohim describes God according to the attribute of justice, Jehovah according to the attribute of mercy, is only in part correct; for even when the advent of God to judgment is announced, He is in general named Jehovah. Rather, אלהים (plur. of אלוהּ, fear), the Revered One, describes God as object; יהוה or יהוה, on the other hand, as subject. אלהים describes Him in the fulness of His glorious majesty, including also the spirits, which are round about Him; יהוה as the Absolute One. Accordingly, Job, when he says יהוה, thinks of God not only as the absolute cause of his fate, but as the Being ordering his life according to His own counsel, who is ever worthy of praise, whether in His infinite wisdom He gives or takes away. Job was not driven from God, but praised Him in the midst of suffering, even when, to human understanding and feeling, there was only occasion for anguish: he destroyed the suspicion of Satan, that he only feared God for the sake of His gifts, not for His own sake; and remained, in the midst of a fourfold temptation, the conqueror.
(Note: In Oliver Goldsmith's Vicar of Wakefield (vid., Jul. Hamberger, Gott und seine Offenbarung, S. 71), there is much that reminds one of the book of Job, especially the repeated misfortunes which befall the worthy clergyman, his submission under all, and the issue which counterbalances his misfortune. But what is copied from the book of Job appears to be only superficial, not to come from the depth of the spiritual life.)
Throughout the whole book he does not go so far as to deny God (אלהים בּרך), and thus far he does not fall into any unworthy utterances concerning His rule.

Shaved - Caused his hair to be shaved or cut off, which was then an usual ceremony in mourning. Worshipped - Instead of cursing God, which Satan said he would do, he adored him, and gave him the glory of his sovereignty, of his justice, and of his goodness also, in this most severe dispensation.