Job 1:5

Now when the days of feasting had run their course, Job sent and sanctified them. He would rise up early in the morning, and he would offer burnt offerings according to the number of them all, because Job said: “It may be that my sons have sinned, and cursed God in their hearts.” Thus Job would do always.
Job 1:5 Modern English Version (MEV)
 
From Albert Barnes’ Notes on the Whole Bible:
 
And it was so, when the days of their feasting were gone about - Dr. Good renders this, “as the days of such banquets returned.” But this is not the idea intended. It is, when the banquets had gone round as in a circle through all the families, “then” Job sent and sanctified them. It was not from an anticipation that they “would” do wrong, but it was from the apprehension that they “might” have sinned. The word rendered “were gone about” (נקף nâqaph) means properly to join together, and then to move round in a circle, to revolve, as festivals do; see the notes at Isaiah 29:1 : “Let the festivals go round.” Here it means that the days of their banqueting had gone round the circle, or had gone round the several families. Septuagint “When the days of the entertainment (or drinking, πότου potou) were finished.” A custom of feasting similar to this prevails in China. “They have their fraternities which they call the brotherhood of the months; this consists of months according to the number of the days therein, and in a circle they go abroad to eat at one another’s houses by turns. If one man has not conveniences to receive the fraternity in his own house, he may provide for them in another; and there are many public houses well furnished for this purpose.” See Semedo’s History of China, i chapter 13, as quoted by Burder in Rosenmuller’s Morgenland. “in loc.”
 
That Job sent - Sent for them, and called them around him. He was apprehensive that they might have erred, and he took every measure to keep them pure, and to maintain the influence of religion in his family.
 
And sanctified them - This expression, says Schultens, is capable of two interpretations. It may either mean that he “prepared” them by various lustrations, ablutions, and other ceremonies to offer sacrifice; or that he offered sacrifices for the purpose of procuring expiation for sins which they might actually have committed. The former sense, he remarks, is favored by the use of the word in Exodus 19:10; 1 Samuel 16:5, where the word means to prepare themselves by ablutions to meet God and to worship him. The latter sense is demanded by the connection. Job felt as every father should feel in such circumstances, that there was reason to fear that God had not been remembered as he ought to have been, and he was therefore more fervent in his devotions, and called them around him, that their own minds might be affected in view of his pious solicitude. What father is there who loves God, and who feels anxious that his children should also, who does not feel special solicitude if his sons and his daughters are in a situation where successive days are devoted to feasting and mirth? The word here rendered “sanctified” (קדשׁ qâdash) means properly to be pure, clean, holy; in Pihel, the form used here, to make holy, to sanctify, to consecrate, as a priest; and here it means, that he took measures to make them holy on the apprehension that they had sinned; that is, he took the usual means to procure for them forgiveness. The Septuagint renders it ἐκάθαριζεν ekatharizen, he purified them.
 
And rose up early in the morning - For the purpose of offering his devotions, and procuring for them expiation. It was customary in the patriarchal times to offer sacrifice early in the morning. See Genesis 22:3; Exodus 32:6.
 
And offered burnt-offerings - Hebrew “and caused to ascend;” that is, by burning them so that the smoke ascended toward heaven. The word rendered “burnt-offerings” (עולה ‛ôlâh) is from עלה ‛âlâh, “to ascend” (the word used here and rendered “offered”), and means that which was made to ascend, to wit, by burning. It is applied in the Scriptures to a sacrifice that was wholly consumed on the altar, and answers to the Greek word ὁλόκαυστον holokauston, “Holocaust.” See the notes at Isaiah 1:11. Such offerings in the patriarchal times were made by the father of a family, officiating as priest in behalf of his household. Thus, Noah officiated, Genesis 8:20; and thus also Abraham acted as the priest to offer sacrifice, Genesis 12:7-8; Genesis 13:18; Genesis 22:13. In the earliest times, and among pagan nations, it was supposed that pardon might be procured for sin by offering sacrifice. In Homer there is a passage which remarkably corresponds with the view of Job before us; Iliad 9:493:
 
The gods (the great and only wise)
 
Are moved by offerings, vows, and sacrifice;
 
Offending man their high compassion wins,
 
And daily prayers atone for daily sins.
 
Pope
 
According to the number of them all - Sons and daughters. Perhaps an additional sacrifice for each one of them. The Septuagint renders this, “according to their numbers, καί μόσχον ἕνα περὶ ἁμαπτίας περὶ τῶν ψυχῶν αὐτῶν kai moschon hena peri hamartias peri tōn psuchōn autōn - a young bullock for sin or a sin-offering for their souls.”
 
It may be that my sons have sinned - He had no positive or certain proof of it. He felt only the natural apprehension which every pious father must, that his sons might have been overtaken by temptation, and perhaps, under the influence of wine, might have been led to speak reproachfully of God, and of the necessary restraints of true religion and virtue.
 
And cursed God in their hearts - The word here rendered curse is that which is usually rendered “bless” ברך bārak. It is not a little remarkable that the same word is used in senses so directly opposite as to “bless” and “to curse.” Dr. Good contends that the word should be always rendered “bless,” and so translates it in this place, “peradventure my sons may have sinned, “nor” blessed God in their hearts,” understanding the Hebrew prefix ו (v) as a disjunctive or negative participle. So too in Job 2:9, rendered in our common translation, “curse God and die,” he translates it, “blessing God and dying.” But the interpretation which the connection demands is evidently that of cursing, renouncing, or forgetting; and so also it is in Job 2:9. This sense is still more obvious in 1 Kings 21:10 : “Thou didst “blaspheme” ברך bārak God and the king.” So also 1 Kings 21:13 of the same chapter - though here Dr. Good contends that the word should be rendered “bless,” and that the accusation was that Naboth “blessed” or worshipped the gods, even Moloch - where he supposes the word מלך melek, should be pointed מלך môlek and read “Molech.” But the difficulty is not removed by this, and after all it is probable that the word here, as in Job 2:9, means to “curse.” So it is understood by nearly all interpreters. The Vulgate indeed renders it singularly enough, “Lest perhaps my sons have sinned, and have blessed God (et benedixerint Deo) in their hearts.” The Septuagint, “Lest perhaps my sons in their mind have thought evil toward God” - κακὰ ἐνεόησαν πρὸς Θεόν kaka enenoēsan pros Theon. The Chaldee, “Lest my sons have sinned and provoked yahweh (יהוה וארגיזדקדם) in their hearts.” Assuming that this is the sense of the word here, there are three ways of accounting for the fact that the same word should have such opposite significations.
 
(1) One is that proposed by Taylor (Concor.), that pious persons of old regarded blasphemy as so abominable that they abhorred to express it by the proper name, and that therefore by an “euphemism” they used the term “bless” instead of “curse.” But it should be said that nothing is more common in the Scriptures than words denoting cursing and blasphemy. The word אלה 'âlâh, in the sense of cursing or execrating, occurs frequently. So the word גדף gâdaph, means to blaspheme, and is often used; 2 Kings 19:6, 2 Kings 19:22; Isaiah 37:6, Isaiah 37:23; Psalms 44:16. Other words also were used in the same sense, and there was no necessity of using a mere “euphemism” here.
 
(2) A second mode of accounting for this double use of the word is. that this was the common term of salutation between friends at meeting and parting. It is then supposed to have been used in the sense of the English phrase “to bid farewell to.” And then, like that phrase, to mean “to renounce, to abandon, to dismiss from the mind, to disregard.” The words χαίρειν chairein, in Greek, and “valere” in Latin, are used in this way. This explanation is suggested by Schultens, and is adopted by Rosenmuller and Noyes, who refer to the following places as parallel instances of the use of the word. Virg. Ecl. 8, 58. “Vivite Sylvoe” - a form, says the Annotator on Virgil (Delphin), of bidding farewell to, like the Greek χαίρετε chairete - “a form used against those whom we reject with hatred, and wish to depart.” Thus, Catull. 11. 17: Cum suis vivat, valeatque moechis. So Aesch. Agam. 574:
 
Kai polla chairein cumforais kataciō.
 
Thus, Plutarch, Dion. p. 975. So Cicero in a letter to Atticus (Psalms 8:8), in which he complains of the disgraceful flight of Pompey, applies to him a quotation from Aristophanes; πολλὰ χαίρειν εἰπὼν τῷ καλῷ polla chairein eipōn tō kalō - “bidding farewell to honour he fled to Brundusium;” compare Ter. And. 4:2. 14. Cicero de Nat. Deor. 1. 44. According to this interpretation, it means that Job apprehended they had renounced God in their hearts. that is, had been unmindful of him, and had withheld from him the homage which was due. - This is plausible: but the difficulty is in making out the use of this sense of the word in Hebrew. That the word was used as a mode of “parting salutation” among the Hebrews is undoubted. It was a solemn form of invoking the divine blessing when friends separated; compare Genesis 28:3; Genesis 47:10. But I find no use of the word where it is applied to separation in the sense of “renouncing,” or bidding farewell to “in a bad sense;” and unless some instances of this kind can be adduced, the interpretation is unsound, and though similar phrases are used in Greek, Latin, and other languages, it does not demonstrate that this use of the word obtained in the Hebrew.
 
(3) A third, and more simple explanation is that which supposes that the original sense of the word was “to kneel.” This, according to Gesenius, is the meaning of the word in Arabic. So Castell gives the meaning of the word - “to bend the knees for the sake of honour;” that is, as an act of respect. So in Syriac, “Genua flexit̂ procubuit.” So “Genu.” the “knee.” Then it means to bend the knee for the purpose of invoking God, or worshipping. In the Piel, the form used here, it means
 
(1) to bless God, to celebrate, to adore;
 
(2) to bless men - that is, to “invoke” blessings on them; to greet or salute them - in the sense of invoking blessings on them when we meet them; 1 Samuel 15:13; Gen 47:7; 2 Samuel 6:20; or when we part from them; Gen 47:10; 1 Kings 8:66; Genesis 24:60;
 
(3) to “invoke evil,” in the sense of “cursing others.” The idea is, that punishment or destruction is from God, and hence, it is “imprecated” on others. In one word, the term is used, as derived from the general sense of kneeling, in the sense of “invoking” either blessings or curses; and then in the general sense of blessing or cursing. This interpretation is defended by Selden, de jure Nat. et Gent. Lib. II. 100:11:p. 255, and by Gesenius, Lexicon. The idea here is, that Job apprehended that his sons, in the midst of mirth, and perhaps revelry, had been guilty of irreverence, and perhaps of reproaching God inwardly for the restraints of virtue and piety. What is more common in such scenes? What was more to be apprehended?
 
Thus did Job continually - It was his regular habit whenever such an occasion occurred. He was unremitted in his pious care; and his solicitude lest his sons should have sinned never ceased - a beautiful illustration of the appropriate feelings of a pious father in regard to his sons. The Hebrew is, “all day;” that is, at all times.