The Madianites sold Joseph in Egypt to Putiphar, an eunuch of Pharao, captain of the soldiers.

And the Midianites sold him into Egypt, to Potiphar, a chamberlain of Pharaoh, the captain of the life-guard.

And the Medanites have sold him unto Egypt, to Potiphar, a eunuch of Pharaoh, head of the executioners.

And in Egypt the men of Midian gave him for a price to Potiphar, a captain of high position in Pharaoh's house.

the Midianites in Egypt sold Joseph to Potiphar, a eunuch of Pharaoh, instructor of the soldiers.

Madanitae autem vendiderunt eum in Aegypto Potiphar satrapae Pharaonis, principi satellitum.

And the Midianites sold him into Egypt It was a sad spectacle, that Joseph should be thus driven from one hand to another. For it added no small indignity to his former suffering, that he is set to sale as a slave. The Lord, however, ceased not to care for him. He even suffered him to be transferred from hand to hand, in order that, at length, it might indeed appear, that he had come, by celestial guidance, to that very dominion which had been promised him in his dreams. Potiphar is called a eunuch, not because he was one really; but because, among the Orientals, it was usual to denote the satraps and princes of the court by that name. The Hebrews are not agreed respecting the dignity which Moses ascribes to him; for some explain it as the "chief of the slaughterers," [1] whom the Greek interpreters follow. But I rather agree with others, who say that he was "the prefect of the soldiers;" not that he had the command of the whole army, but because he had the royal troops under his hand and authority: such are now the captains of the guard, if you join with it another office which the prefects of the prison exercise. For this may be gathered from Genesis 39:1 [2]

Footnotes

1 - The term applies primarily to butchers, who slaughter animals for food; then to persons who slaughter animals for sacrifice; and then to executioners who put men to the slaughter under the authority of the monarch or the state. -- Ed.

2 - See ver. 20 The words rendered "prefects of the prison," are praefecti hospitii -- and in the French, Prevosts de l'hostel -- perhaps, prefects of the town-house, or town-hall, would have been more correct. The expression in the original, sr-htvchym, sar-hatabachim, means the captain of the executioners; that is, of the king's body guard, whose office it was to inflict capital punishments; as in the Turkish court at present. -- See Gesenius' Lexicon. -- Ed

Potiphar, an officer of Pharaoh's - The word סריס saris, translated officer, signifies a eunuch; and lest any person should imagine that because this Potiphar had a wife, therefore it is absurd to suppose him to have been a eunuch, let such persons know that it is not uncommon in the east for eunuchs to have wives, nay, some of them have even a harem or seraglio where they keep many women, though it does not appear that they have any progeny; and probably discontent on this ground might have contributed as much to the unfaithfulness of Potiphar's wife, as that less principled motive through which it is commonly believed she acted.
Captain of the guard - שר הטבחים sar kattabbachim, chief of the butchers; a most appropriate name for the guards of an eastern despot. If a person offend one of the despotic eastern princes, the order to one of the life-guards is, Go and bring me his head; and this command is instantly obeyed, without judge, jury, or any form of law. Potiphar, we may therefore suppose, was captain of those guards whose business it was to take care of the royal person, and execute his sovereign will on all the objects of his displeasure. Reader, if thou hast the happiness to live under the British constitution, be thankful to God. Here, the will, the power, and utmost influence of the king, were he even so disposed, cannot deprive the meanest subject of his property, his liberty, or his life. All the solemn legal forms of justice must be consulted; the culprit, however accused, be heard by himself and his counsel; and in the end twelve honest, impartial men, chosen from among his fellows, shall decide on the validity of the evidence produced by the accuser. For the trial by jury, as well as for innumerable political blessings, may God make the inhabitants of Great Britain thankful!
1. With this chapter the history of Joseph commences, and sets before our eyes such a scene of wonders wrought by Divine Providence in such a variety of surprising instances, as cannot fail to confirm our faith in God, show the propriety of resignation to his will, and confidence in his dispensations, and prove that all things work together for good to them that love him. Joseph has often been considered as a type of Christ, and this subject in the hands of different persons has assumed a great variety of coloring. The following parallels appear the most probable; but I shall not pledge myself for the propriety of any of them: "Jesus Christ, prefigured by Joseph, the beloved of his father, and by him sent to visit his brethren, is the innocent person whom his brethren sold for a few pieces of silver, the bargain proposed by his brother Judah, (Greek Judas), the very namesake of that disciple and brother (for so Christ vouchsafes to call him) who sold his Lord and Master; and who by this means became their Lord and Savior; nay, the Savior of strangers, and of the whole world; which had not happened but for this plot of destroying him, the act of rejecting, and exposing him to sale. In both examples we find the same fortune and the same innocence: Joseph in the prison between two criminals; Jesus on the cross between two thieves. Joseph foretells deliverance to one of his companions and death to the other, from the same omens: of the two thieves, one reviles Christ, and perishes in his crimes; the other believes, and is assured of a speedy entrance into paradise. Joseph requests the person that should be delivered to be mindful of him in his glory; the person saved by Jesus Christ entreats his deliverer to remember him when he came into his kingdom." - See Pascal's Thoughts. Parallels and coincidences of this kind should always be received cautiously, for where the Spirit of God has not marked a direct resemblance, and obviously referred to it as such in some other part of his word, it is bold, if not dangerous, to say "such and such things and persons are types of Christ." We have instances sufficiently numerous, legitimately attested, without having recourse to those which are of dubious import and precarious application. See the observation on Genesis 40. (Genesis 40:23 (note)).
2. Envy has been defined, "pain felt, and malignity conceived, at the sight of excellence or happiness in another." Under this detestable passion did the brethren of Joseph labor; and had not God particularly interposed, it would have destroyed both its subjects and its object, Perhaps there is no vice which so directly filiates itself on Satan, as this does. In opposition to the assertion that we cannot envy that by which we profit, it may be safely replied that we may envy our neighbor's wisdom, though he gives us good counsel; his riches, though he supplies our wants; and his greatness, though he employs it for our protection.
3. How ruinous are family distractions! A house divided against itself cannot stand. Parents should take good heed that their own conduct be not the first and most powerful cause of such dissensions, by exciting envy in some of their children through undue partiality to others; but it is in vain to speak to most parents on the subject; they will give way to foolish predilections, till, in the prevailing distractions of their families, they meet with the punishment of their imprudence, when regrets are vain, and the evil past remedy.

And the Midianites sold him into Egypt unto Potiphar, an (l) officer of Pharaoh's, [and] captain of the guard.
(l) Or "eunuch", which does not always signify a man that is gelded, but also someone that is in some high position.

And the Midianites sold him into Egypt,.... Or Medanites, who sprung from Medan, a brother of Midian, and son of Keturah, Genesis 24:2; and were distinct from the Midianites, though they dwelt near them, and were now in company with them, and with the Ishmaelites, and were all concerned in the buying and selling of Joseph, and therefore this is sometimes ascribed to the one, and sometimes to the other:
unto Potiphar, an officer of Pharaoh; the word is sometimes used for an eunuch, but cannot design one here, since Potiphar had a wife, and some say a child; but he either was a chamberlain, or however some officer at court, besides what follows:
and captain of the guard; of Pharoah's guard, his bodyguard; some render it, "of the slaughterers" (h); meaning either cooks or butchers, of whom he was the chief; or rather executioners, he having the charge of prisoners, and the care of executing them, like our sheriffs. Joseph was a most eminent type of Christ, and there are so many things in this chapter which show an agreement between them that cannot be passed over. Joseph was the son of his father's old age, Christ the son of the Ancient of days; Joseph was in a peculiar manner beloved by his father, Christ is the dear son of his Father's love; Jacob made for Joseph a coat of many colours, God prepared a body in human nature for Christ, filled and adorned with the various gifts and graces of the Spirit without measure. Joseph was hated by his brethren, and they could not endure to think he should have the dominion over them. The Jews, of whom Christ was according to the flesh, hated him, and would not have him to reign over them; Joseph was sent by his father a long journey to visit his brethren, and know the welfare of them and their flocks, Christ was sent from heaven to earth to seek and save the lost sheep of the house of Israel; Joseph's brethren, when they saw him come to them, conspired to take away his life, the Jews, who were Christ's own, when he came to them, received him not, but said, this is the heir, let us kill him, and they consulted to take away his life; Joseph was stripped of his clothes, and sold for twenty pieces of silver at the motion of Judah, and Christ, by one of the same name, was sold for thirty pieces of silver, and was stripped of his clothes by the Roman soldiers; Joseph was delivered into the hands of foreigners, and Christ into the hands of the Gentiles; Joseph being reckoned as dead by his father, and yet alive, may be herein an emblem of Christ's death, and his resurrection from the dead.
(h) Sept. "principi coquorum", Cartwright; so Josephus, "principi lanionum", Pagninus, Montanus, "capitalium rerum praefecto", Tigurine version.

But Joseph, while his father was mourning, was sold by the Midianites to Potiphar, the chief of Pharaoh's trabantes, to be first of all brought low, according to the wonderful counsel of God, and then to be exalted as ruler in Egypt, before whom his brethren would bow down, and as the saviour of the house of Israel. The name Potiphar is a contraction of Poti Pherah (Genesis 41:50); the lxx render both Πετεφρής or Πετεφρῆ (vid., Genesis 41:50). סריס (eunuch) is used here, as in 1-Samuel 8:15 and in most of the passages of the Old Testament, for courtier or chamberlain, without regard to the primary meaning, as Potiphar was married. "Captain of the guard" (lit., captain of the slaughterers, i.e., the executioners), commanding officer of the royal body-guard, who executed the capital sentences ordered by the king, as was also the case with the Chaldeans (2-Kings 25:8; Jeremiah 39:9; Jeremiah 52:12. See my Commentary on the Books of Kings, vol. i. pp. 35, 36, Eng. Tr.).