And when Sara had seen the son of Agar the Egyptian playing with Isaac her son, she said to Abraham:

“See, I ask you, dearly beloved, in this instance once again Sarah not tolerating the brashness of Ishmael and unable to put up equably with the maidservant's son being reared with Isaac. So just as she previously wished to check Hagar's arrogance and in her extreme irritation had her sent packing, so in this case too she wanted to nip Ishmael's forwardness in the bud. Not bearing to see the son born of grace and of the very gift of God being reared along with that of the Egyptian maidservant, she said to Abraham, "Send away the maidservant and her son: surely the son of the maidservant will not share the inheritance with my son?" Since she realized that she herself was in fact in extreme old age, and she saw the patriarch was well on (after all, they were both advanced in years), she was afraid that in the event of their sudden passing Ishmael would, on the score of his being born of an association of the patriarch, endeavor to thrust himself into his father's inheritance and become a sharer of it with Isaac. Hence she said, "Send away from here the maidservant and her son." Let her learn at this stage, she is saying, that the son of the maidservant has nothing in common with my son, Isaac. It is, in fact, not fair that the slave's son should be reared with that of the mistress, my son.”

“מצחק MAKING SPORT — This means worshipping idols, as it is said in reference of the Golden Calf, (Exodus 32:6) “And they rose up to make merry (לצחק).” Another explanation is that it refers to immoral conduct, just as you say in reference to Potiphar’s wife, (Genesis 39:17) “To mock (לצחק) at me.” Another explanation is that it refers to murder, as (2 Samuel 2:14) “Let the young men, I pray thee, arise and make sport (וישחקו) before us” (where they fought with and killed one another) From Sarah’s reply — “for the son of this bondwoman shall not be heir with my son״ — you may infer that he (Ishmael) was quarrelling with Isaac about the inheritance, saying, “I am the first-born and will, therefore, take a double portion”. They went into the field and he (Ishmael) took his bow and shot arrows at him (Isaac), just as you say (Proverbs 26:18-19) “As a madman who casteth firebrands, [arrows and death] and says: I am only מצחק mocking” (Genesis Rabbah 53:11).”

“‘METZACHEIK’ (MAKING SPORT). This refers to worshipping idols, murder and sexual immorality. He [Ishmael] quarrelled with Isaac about inheritance, saying, “I am the first-born and will take a double portion.” They then went into the field, and Ishmael took his bow and shot arrows at Isaac, just as you say, As a madman who casteth firebrands, arrows and death, so is the man who deceiveth his neighbor, and saith, Am I not in sport? It is from Sarah’s complaint to Abraham — for the son of this bondwoman shall not be heir, etc. — that you learn [that they were quarrelling about the inheritance]. All this is Rashi’s language. Here too, the Rabbi writes all the different opinions, [mentioned in the following]: “We have been taught: Rabbi Shimon the son of Eleazar said, ‘There are four interpretations of Rabbi Akiba which I interpret differently, and my interpretation seems more acceptable than his. Rabbi Akiba interpreted: “And Sarah saw the son of Hagar the Egyptian, whom she had borne unto Abraham, making sport. Making sport is but a designation for idolatry, etc.” But I say Heaven forbid that such be in the house of the righteous one! Is it possible that he, of whom it was written, For I have known him, to the end that he may command his children and his household, etc., will have in his household idolatry, sexual immorality, and murder? Making sport mentioned here is but a designation for the inheritance. When Isaac was born and everyone rejoiced, Ishmael said to them, “Fools, I am the first-born, and I take a double portion.” From the complaint of our mother Sarah to Abraham you learn [that making sport refers to the inheritance]. And my interpretation seems more acceptable than that of Rabbi Akiba.’” The expression of the Rabbi, “that Ishmael quarrelled with Isaac about the inheritance,” also does not appear correct for if so, this must have happened much later when Isaac was grown up, and Ishmael would then have been too big for his mother to carry him on her shoulder. Our Rabbis have also said that Ishmael was seventeen years old [at the time he left his father’s house]. If so, this happened at the time when Isaac was weaned, [and Isaac was thus too young for Ishmael to quarrel with him about the inheritance]. Rabbi Abraham ibn Ezra said in line with the literal interpretation of Scripture that metzachek means “playing,” as is normal for every boy, and she was jealous of him because he was bigger than her son. The correct interpretation appears to me to be that this event took place on the day that Isaac was weaned, and Sarah saw Ishmael mocking Isaac or the great feast. It is for this reason that the verse says, And Sarah saw the son of Hagar the Egyptian — rather than Ishmael — making sport. Similarly, she said, Cast out this bondwoman and her son, for she said: “The slave who mocks his master is deserving of death or stripes, but I want only that you cast him out from before me, and that he should in no way inherit your belongings together with my son, who is the son of the mistress.” She also told Abraham to cast out his mother, as the boy was unable to leave her for he would die if he were to leave his mother.”

“The casting out of Ishmael is here considered of, and resolved on. I. Ishmael himself gave the occasion by some affronts he gave to Isaac his little brother, some think on the day that Abraham made the feast for joy that Isaac was safely weaned, which the Jews say was not till he was three years old, others say five. Sarah herself was an eye-witness of the abuse: she saw the son of the Egyptian mocking (Gen 21:9), mocking Isaac, no doubt, for it is said, with reference to this (Gal 4:29), that he that was born after the flesh persecuted him that was born after the Spirit. Ishmael is here called the son of the Egyptian, because, as some think, the 400 years' affliction of the seed of Abraham by the Egyptians began now, and was to be dated hence, Gen 15:13. She saw him playing with Isaac, so the Septuagint, and, in play, mocking him. Ishmael was fourteen years older than Isaac; and, when children are together, the elder should be careful and tender of the younger: but it argued a very base and sordid disposition in Ishmael to be abusive to a child that was no way a match for him. Note, 1. God takes notice of what children say and do in their play, and will reckon with them if they say or do amiss, though their parents do not. 2. Mocking is a great sin, and very provoking to God. 3. There is a rooted remaining enmity in the seed of the serpent against the seed of the woman. The children of promise must expect to be mocked. This is persecution, which those that will live godly must count upon. 4. None are rejected and cast out from God but those who have first deserved it. Ishmael is continued in Abraham's family till he becomes a disturbance, grief, and scandal to it. II. Sarah made the motion: Cast out this bond-woman, Gen 21:10. This seems to be spoken in some heat, yet it is quoted (Gal 4:30) as if it had been spoken by a spirit of prophecy; and it is the sentence passed on all hypocrites and carnal people, though they have a place and a name in the visible church. All that are born after the flesh and not born again, that rest in the law and reject the gospel promise, shall certainly be cast out. It is made to point particularly at the rejection of the unbelieving Jews, who, though they were the seed of Abraham, yet, because they submitted not to the gospel covenant, were unchurched and disfranchised: and that which, above any thing, provoked God to cast them off was their mocking and persecuting the gospel church, God's Isaac, in its infancy, Th1 2:16, Note, There are many who are familiarly conversant with the children of God in this world, and yet shall not partake with them in the inheritance of sons. Ishmael might be Isaac's play-fellow and school-fellow, yet not his fellow-heir. III. Abraham was averse to it: The thing was very grievous in Abraham's sight, Gen 21:11. 1. It grieved him that Ishmael had given such a provocation. Note, Children ought to consider that the more their parents love them the more they are grieved at their misconduct, and particularly at their quarrels among themselves. 2. It grieved him that Sarah insisted upon such a punishment. "Might it not suffice to correct him? would nothing less serve than to expel him?" Note, Even the needful extremities which must be used with wicked and incorrigible children are very grievous to tender parents, who cannot thus afflict willingly. IV. God determined it, Gen 21:12, Gen 21:13. We may well suppose Abraham to be greatly agitated about this matter, loth to displease Sarah, and yet loth to expel Ishmael; in this difficulty God tells him what his will is, and then he is satisfied. Note, A good man desires no more in doubtful cases than to know his duty, and what God would have him do; and, when he is clear in this, he is, or should be, easy. To make Abraham so, God sets this matter before him in a true light, and shows him, 1. That the casting out of Ishmael was necessary to the establishment of Isaac in the rights and privileges of the covenant: In Isaac shall thy seed be called. Both Christ and the church must descend from Abraham through the loins of Isaac; this is the entail of the promise upon Isaac, and is quoted by the apostle (Rom 9:7) to show that not all who come from Abraham's loins were the heirs of Abraham's covenant. Isaac, the promised son, must be the father of the promised seed; therefore, "Away with Ishmael, send him far enough, lest he corrupt the manners or attempt to invade the rights of Isaac." It will be his security to have his rival banished. The covenant seed of Abraham must be a peculiar people, a people by themselves, from the very first, distinguished, not mingled with those that were out of covenant; for this reason Ishmael must be separated. Abraham was called alone, and so must Isaac be. See Isa 51:2. It is probable that Sarah little thought of this (Joh 11:51), but God took what she said, and turned it into an oracle, as afterwards, Gen 27:10. 2. That the casting out of Ishmael should not be his ruin, Gen 21:13. He shall be a nation, because he is thy seed. We are not sure that it was his eternal ruin. It is presumption to say that all those who are left out of the external dispensation from all his mercies: those may be saved who are not thus honoured. However, we are sure it was not his temporal ruin. Though he was chased out of the church, he was not chased out of the world. I will make him a nation. Note, (1.) Nations are of God's making: he founds them, he forms them, he fixes them. (2.) Many are full of the blessings of God's providence that are strangers to the blessings of his covenant. (3.) The children of this world often fare the better, as to outward things, for their relation to the children of God.”

“Wherefore she said unto Abraham, cast out this bondwoman and her son,.... Hagar, Sarah's handmaid and bondservant, and her son Ishmael; by this it appears that Hagar was concerned in this affair, and set her son on to mock Isaac, at least she encouraged him in it, buoying: him up with his being the firstborn, and having a right to the inheritance; wherefore Sarah saw plainly that there would be no peace nor comfort for her and her son, unless Hagar and her son were turned out of doors, for which she moves Abraham; and this not merely in a passion, but by divine direction and influence, as is evident from God's approbation of it: for the son of this bondwoman shall not be heir with my son, even with Isaac; which he would seem to be, if continued, and would think himself so, and there would be continual bickerings about it; wherefore, to put it out of all doubt who was heir, she desires that he and his mother both might be cast out of the house, which would be a clear determination of this matter. Sarah may seem to take upon her too much, to be so peremptory, as to declare who should, and who should not be heir, which more properly belonged to Abraham, whom she called her lord, Gen 18:12; but what will sufficiently free her from any charge of this kind is the revelation of the divine will, and the promise of God that so it should be; namely, that the covenant God had so often renewed with Abraham should be established with Isaac, and not with Ishmael, Gen 17:19. Now what was the design of God, in guiding Sarah to make such a motion as this to Abraham, is taught us by the Apostle Paul, who makes these two women to be types and figures of the two covenants, and their sons of those that are under them, see Gal 4:22.”

“Mocking - What was implied in this mocking is not known. St. Paul, Gal 4:29, calls it persecuting; but it is likely he meant no more than some species of ridicule used by Ishmael on the occasion, and probably with respect to the age of Sarah at Isaac's birth, and her previous barrenness. Jonathan ben Uzziel and the Jerusalem Targum represent Ishmael as performing some idolatrous rite on the occasion, and that this had given the offense to Sarah. Conjectures are as useless as they are endless. Whatever it was, it became the occasion of the expulsion of himself and mother. Several authors are of opinion that the Egyptian bondage of four hundred years, mentioned Gen 15:13, commenced with this persecution of the righteous seed by the son of an Egyptian woman.”

“Playing, or persecuting, as St. Paul explains it, Galatians iv. 29. The play tended to pervert the morals of the young Isaac, whether we understand this term metsachak, as implying idolatry, or obscene actions, or fighting; in all which senses it is used in Scripture. See Exodus xxxii. 6; Genesis xxvi. 8; 2 Kings ii. 14. (Menochius) Ismael was 13 years older than Isaac; and took occasion, perhaps, from the feast, and other signs of preference given by his parents to the latter, to hate and persecute him, which Sara soon perceiving, was forced to have recourse to the expedient apparently so harsh, of driving Ismael and his mother from the house, that they might have an establishment of their own, and not disturb Isaac in the inheritance after the death of Abraham. (Haydock) — In this she was guided by a divine light; (Menochius) and not by any female antipathy, ver. 12. Many of the actions of worldlings, which at first sight may appear innocent, have a natural and fatal tendency to pervert the morals of the just; and therefore, we must keep as much as possible at a distance from their society. — With Isaac her son. Hebrew has simply mocking, without mentioning what. But the sequel shews the true meaning; and this addition was found in some Bibles in the days of St. Jerome, as he testifies, and is expressed in the Septuagint. (Haydock) — Ismael was a figure of the synagogue, which persecuted the Church of Christ in her birth. (Du Hamel)”