Génesis 18:14 Midrash: Ein Yaakov (Glick Edition), Midrash Tanchuma, Midrash Tanchuma Buber & Aggadat Bereshit

Isaac was born on Passover. Whence do we infer this? It is written (Gen. 18, 14) At the next festival I will return to thee, and Sarah will have a son. What festival was it when he said this? Shall I assume that it was Passover, that he referred to Pentecost? Is it possible to bear children after fifty days' gestation? If I assume that it was Pentecost, that he referred to Tishri, then again the question is, Who bears children after five months' gestation? Shall I assume that it was Tabernacles, and that he referred to Passover, the same objection may be made: Is it possible to bear children after: six months of gestation? We have been taught in a Baraitha [in answer to the last objection]; that particular year was a leap year [and, therefore, it makes seven months]. But at all events the objection remains, for we must deduct the days of menstruation; hence less than seven months will remain. Mar Zutra [in answer to this] said that although a child born after nine months' gestation is never born before the ninth month is completed, nevertheless a seven months' child can he born before the seventh month is complete; as it is said (I Sam. 1, 20) And it came to pass, Li't'kufoth Hayamim (when the time was come about); the minimum of T'kufoth are two and the minimum of yamim is also two (i.e., after six months and two days' gestation, child-birth is possible).

(Lev. 7:11:) “This is the law of the sacrifice for peace offerings.” You find that all of the [other] sacrifices that they would bring, they would bring for sins. In the case of the guilt offerings, they would sacrifice them for sins, as stated (in Ezra 10:19), “And they gave their word (literally, their hand) that they would put away their wives; and being guilty, [they gave] a ram of the flock for their guilt.” Now the sin offering [took place] for the unintentional sin, as stated (in Numb. 15:25), “and their sin offering before the Lord for their unintentional sin.” A burnt offering took place for a thought of the heart. Thus it is stated (in Job 1:5), “and rising early in the morning, he would offer burnt offerings, one for each of them, for Job said, ‘Perhaps my children have sinned and blasphemed God in their hearts.’” But when the thank offering took place, it took place on account of their gratitude. The Holy One, blessed be He, said, “This is the dearest to Me of all the offerings.” David said (in Ps. 50:23), “Whoever sacrifices a thank offering honors Me (ykbdnni).” It does not say ykbdni but ykbdnni, [spelled with n] two times, [once] for this world and [once] for the world to come.²⁰Lev. R. 9:2; Rashi on Sanh. 43b. R. Judah said, “Whoever answers amen in this world merits answering amen in the world to come. Where is it shown? (In Ps. 41:14), ‘Blessed be the Lord, the God of Israel, from everlasting to everlasting (literally: from the world and unto the world); amen and amen.’ What is the meaning of ‘amen and amen?’ Amen in this world and amen in the world to come.” Ergo (in Ps. 50:23), “Whoever sacrifices a thank offering honors Me.” R. Aqiva said, “Whoever speaks songs [of praise] in this world merits speaking songs [of praise] in the world to come, as stated (Exodus 15:1), ‘Then Moshe sang (literally, will sing).’ It does not say, ‘Then he sang,’ but rather, ‘Then he will sing.’ Ergo, whoever speaks songs [of praise] in this world merits speaking songs [of praise] in the world to come.” Therefore, it is stated, (in Ps. 50:23), “Whoever sacrifices a thank offering honors Me.” (Lev. 7:11:) “This is the law of the sacrifice for peace offerings.” Peace offerings are great because they make peace between Israel and their Father in heaven. Eleazar Haqappar says, “Peace is great, because even though Israel worships idols but [still] forms one fellowship (havurah), strict justice does not harm them.²¹Numb. R. 11:17; cf. Gen. R. 38:6 It is so stated (in Hos. 4:17), ‘Ephraim is associated (havur) with idols. Let him be.’” R. Levi says, “Peace is great, because there is no conclusion to the priestly blessing other than peace, as stated (in Numb. 6:26), ‘and grant you peace.’” R. Simeon ben Gamaliel said, “Peace is great, because the Holy One, blessed be He, has written things in the Torah that did not happen, which are there only because of peace.²²yPe’ah 1:1 (16a); see Gen. R. 48:18; 100:8; Lev. R. 9:9; Deut. R. 5:5; Yev. 65b. They are the following: When Jacob had died (Gen. 50:15), ‘And Joseph's brothers saw that their father was dead, and they said, “Perhaps Joseph begrudges us.”’ What did they do?²³Above, Exod. 1:2. They went to Bilhah and said to her, ‘Go in unto Joseph and say to him (in Gen. 50:16), “Before he died, your father gave a command saying, ‘So shall you say to Joseph, “Please forgive the transgression of your brothers.”’”’ Now Jacob never commanded any of these things at all; yet they said this thing on their own.” Rabban Simeon ben Gamaliel said, “See how much ink was spilled, how many pens²⁴Gk.: kalamoi. were broken, how many skins were prepared, and how many children were whipped in order to learn something which did not happen which is in the Torah. See how great is the power of peace!” And so you find in the case of Sarah, when the ministering angels came to Abraham and said to him (in Gen. 18:14), ‘At the set time I will return unto you, at the time that life is due.’ At that time (according to Gen. 18:12), ‘Sarah laughed to herself, saying, “… and my husband is an old man.”’ The Holy One, blessed be He, said to Abraham (in vs. 13), ‘[But] why did Sarah laugh, saying, “Is it true that I also shall bear [a child] when I am old?”’²⁵Thus for the sake of peace the Holy One hid from Abraham the fact that Sarah had called him an old man. Now why all this? For the sake of peace.” Also in the world to come, when the Holy One, blessed be He, returns the diaspora to Jerusalem, He shall return them in peace. Thus it is stated (in Ps. 122:6), “Pray for the peace of Jerusalem, may those who love you have serenity.” And so it says (in Is. 66:12), “Behold, I will extend peace unto her like a river.”

When Jacob had died, (Gen. 50:15:) AND JOSEPH'S BROTHERS SAW THAT THEIR FATHER WAS DEAD…, what did they do?³⁵Above, Exod. 1:2. They went to Bilhah and said to her: Go in unto Joseph and say to him (in Gen. 50:16): BEFORE HE DIED YOUR FATHER GAVE A COMMAND SAYING.³⁶The command was for Joseph to forgive his brothers and so make peace. Now Jacob never commanded any of these things at all; yet they said this thing on their own. Rabban Simeon ben Gamaliel said: See how much ink was spilled, how many pens³⁷Gk.: kalamoi. were broken, {how many children were whipped,} how many skins were {destroyed} [prepared], [and how many children were whipped], in order to learn something which was not in the Torah. See how great is the power of peace!
And so you find in the case of Sarah, when the ministering angels came to Abraham and said to him (in Gen. 18:14): AT THE SET TIME I WILL RETURN UNTO YOU, AT THE TIME THAT LIFE IS DUE, AND SARAH SHALL HAVE A SON, at that time (according to Gen. 18:12) SARAH LAUGHED TO HERSELF, SAYING:… [AND MY HUSBAND IS AN OLD MAN]. The Holy One said to Abraham (in vs. 13): [But] WHY DID SARAH LAUGH, SAYING: IS IT TRUE THAT I ALSO SHALL BEAR < A CHILD > WHEN I AM OLD?³⁸Thus for the sake of peace the Holy One hid from Abraham the fact that Sarah had called him an old man. Now why all this? For the sake of peace.