What is the corollary between Yitzchak marrying Rivkah, and the fact that he was forty years old when he married her? Why was age 40 the appropriate time for Yitzchak to marry?
Malbim: He waited until he was 40 to marry, until the boiling passion [of youth] cooled off and his intellect was complete, so he could father someone like himself, who will be proper to found Klal Yisrael. Rivkah, his Zivug, was proper for this.
Ha'amek Davar: Until he was 40, there was no one proper for him.
Gur Aryeh #1 (to 26:34): When the average lifespan is 70 years, Chazal designated age 18 as the time to marry (Mishnah Avos 5:21) - which is at approximately one quarter of a person's lifetime. In Yitzchak's times, the average lifespan was 158 (Yitzchak would live to 180, and Yishmael to 137) - one quarter of which is age 40. A person's lifetime is comparable to the four solar seasons. After the winter solstice, the sun must approach us by a full quarter of its revolution until spring, when the trees first begin to produce fruit. So too, a person begins to bear children at a quarter of his lifespan.
Gur Aryeh #2 (to 26:34): The number 40 represents wholeness, ten times the four directions. Yitzchak would approach his mate in wholeness, as appropriate for Yitzchak's trait of Din. 4
Which we know since Sarah was 90 when she bore him, and 127 at the time (right before her death).
Ohr ha'Chayim: The Torah teaches this to dispel criticism against Avraham or Yitzchak for delaying his marriage. Also see Gur Aryeh (refer to 25:20:1.1:1 and the notes there).
Moshav Zekenim asks - "Na'arah" connotes at least 12! Rather, Rivkah was 14 when she married Yitzchak. Then, she lived to be 133, like the Sifrei (Devarim, 357:7). She was 11 at the time of the Akeidah. It is not normal to inform people about a baby, rather, an attractive Na'arah. We must say that the Midrashim argue. (Also refer to 25:20:1.3:1*.) Da'as Zekenim asks - If Rivkah was 14, how does the Gemara learn from her that a Na'arah gets a year to prepare for Chupah? (Perhaps she physically matured after age 13 and a half, so she was truly a Na'arah, like the verse says! - PF.)
According to Maharal, Sheleimus is an essential aspect of Din / Mishpat; see Nesivos Olam, Nesiv ha'Din, Ch. 2.
Don't we already know the name of Rivkah's father and brother, and her place of origin? Why does the Torah see fit to repeat it here?
Seforno: The Torah writes that she was Lavan's sister, to teach us why (based on the principle 'Most children resemble their maternal uncle'), she bore a wicked son like Esav. 4
Ohr ha'Chayim #1: This is to teach why HaSh-m answered Yitzchak, and not her, because she was a Tzadekes bas Rasha. It repeats her brother to explain why she gave birth to a Rasha. Most children resemble the mother's brother.
Ohr ha'Chayim #2: It repeats her brother to explain why she was barren, and needed Tefilah - it was due to her brother's Berachah, lest people say that a Rasha's Berachah helped (refer to 24:60:151:1).
Malbim: The Torah stresses that she was from Avraham's family, for just like plants thrive only in their native land, but not far away, and not if grafted onto a different species, so too people. This is why he was adamant that she be from his family 5 and birthplace.
Moshav Zekenim: We say that the Torah mentions the brother of Yishmael's daughter (28:9) to teach about Yaakov's years; and it mentions Elisheva's brother (Shemos 6:23) to teach that one should check a girl's brothers before marrying her! Neither of those is applicable to expound here.
Malbim: People are corrupted due to three things - bad parents, a bad locale, and bad companions. She had all three, and did not learn from them! Compare to Gur Aryeh; refer to 25:20:2.2:1.
Oznayim la'Torah: In similar fashion, at the end of the Parshah (28:9), the Torah inserts similar details with regard to Yishmael, the father of Machalas, yet Rashi makes a different comment (Refer to 28:9:3:1)? This is because Rivkah was a Tzadekes, so it is correct to expound whatever possible in her praise, which is not the case by Machalas bas Yishmael. See Oznayim la'Torah who adds another reason why here, Rashi makes the Derashah that he does.
Oznayim la'Torah: This was to counter the mockers, who claimed that Yaakov and Esav were the grandsons of Avimelech - i.e. that Yaakov resembled Sarah; and Esav resembled Avimelech. Therefore the Torah points out that, to understand how Rivkah could have a son like Esav, one need look no further than her brother, Lavan.
Why does the Torah call Aram Naharayim, "Padan Aram"?
Rashi #1: Because there were two Arams - Aram Naharayim and Aram Tzovah (Syria), so the Torah refers to it as 'a pair of Arams,' 1 like Tzemed Bakar (a pair of oxen, in Shmuel I 11:7), which is translated "Padan Torin."
Rashi #2: It means simply 'the field of Aram.' 2
Why does it say both "Lavan ha'Arami" and "mi'Padan Aram"?
Rashi: To teach us that he was from Padan Aram and not from Aram Tzovah (Syria). Refer to 25:20:3:1.
Ohr ha'Chayim, Oznayim la'Torah #1 (citing the Midrash Rabah): 'Ha'Arami' means the swindler. 1
Oznayim la'Torah #2: To inform us that Besu'el was from the place called Aram; and not that he was a descendent of Aram, the son of Shem. 2
Why does it say "Lo l'Ishah"?
Ohr ha'Chayim: She was his destined Zivug (mate), therefore he married her without checking into her brother.
Ha'amek Davar: She will help him in his ways. He was not concerned lest it will not be a good match due to the cruel nature of people of Aram.
QUESTIONS ON RASHI
Rashi writes: "'[Yitzchak was] forty years old' - ... He waited until Rivkah was three... and he married her." Why does Rashi tell us Rivkah's age at this point?
Rashi writes: "Yitzchak was 37 years old [at the Akeidah], and Rivkah was born at that time." Rashi learns this way because Avraham was informed of her birth immediately after the Akeidah (22: 20-23). But many other descendants of Nachor are mentioned there, who could not have all been born just then! Why does Rashi make this assumption?
Gur Aryeh: The term "Avraham was informed (va'Yugad)" (22:20) implies that he was told news that had just happened [and the main content was that Rivkah was born]. 1 The other sons of Nachor are mentioned there for a different reason, to show how his family was parallel in number to Avraham's family. Nachor had 12 sons - 8 from his wife Milkah, and 4 from his concubine, parallel to the twelve tribes of Yaakov. 2 This highlighted how Rivkah was in fact the destined match for Yitzchak.
Rashi writes: "He waited until Rivkah was three... and he married her."But Bereishis 24 often refers to her as a Na'arah (which usually means age 12)?
Gur Aryeh: Physically, her limbs had grown to the build of a Na'arah. 1
Rashi writes: "He waited until Rivkah was three... and he married her." Why then did the verse (24:16) need to emphasize that she was a Besulah?
Gur Aryeh (to 24:16): Avraham waited until three years after hearing the news, before sending Eliezer, so she was actually over three years old. Rashi means that she was not yet in her fourth year.
Rashi writes: ""He waited until Rivkah was three... and he married her." How could he have married a minor? Chazal teach that doing so can delay the redemption, for she cannot yet bear children?
Gur Aryeh #1: Yitzchak (at that time) was physically barren, and himself unable to father children (Yevamos 64a).
Gur Aryeh #2: It was clear that HaSh-m had miraculously arranged the match (24:50), so it was permitted to him, since it was the will of HaSh-m. 1
Rashi writes: "This verse tells Rivkah's praises; she was the daughter and sister of evildoers, from a city of evildoers; yet she did not learn their ways." Do we not know this already from the Torah's account?
Mizrachi: Yes, we would know; but this verse is coming to tell her praises.
Gur Aryeh: We might have thought that she turned out righteous because of her young age when she left her father's home; that she was not yet intelligent enough to pick up on his evil ways. The verse comes to praise her, to show that she was intelligent, and she consciously rejected their negative influence.
Rashi writes: "She was the daughter of a Rasha, the sister of a Rasha, and from a city of Resha'im; yet she did not learn their ways." If she did not learn from her father, certainly she would not learn from her brother or town; so why are these added?
Gur Aryeh #1: There are three ways that a person might be influenced to act negatively - out of fear (e.g. of a parent), 1 love (of a sibling), or by habit of the local custom. Rivkah followed none of these, which shows her great righteousness and purity of spirit.
Gur Aryeh #2: There are three types of association between two entities- cause, commonality, and recipient [in this case, environment]. A parent is a person's cause, a sibling shares common flesh and blood, 2 and one's home-town accepts him - and Rivkah abandoned them all.
Maharal (Nesivos Olam, Nesiv Ahavas HaSh-m, beg. of Ch.1): A son's relationship to his father is primarily one of fear, not of love.
Maharal (Be'er ha'Golah, beg. of Be'er #6): A brother and sister are like one entity; whereas a father and daughter are not equivalent, for one is the cause, and the other the outcome.