Who are the Pilagshim (concubines) mentioned here?
Rashbam, Ramban and Targum Yonasan: Hagar and Keturah..
Since "ha'Pilagshim" is written without a 'Yud' (before the 'Mem,' to denote singular) - though our texts do have a ?Yud?..
Why does the Torah refer to Keturah, whom Avraham married ? See Pasuk #1.25:1 - as a Pilegesh?
Ramban: Since the Torah wrote ? in Vayeira, 21:12 "Ki be?Yitzchak Yikarei l?cha Zara? any other wives that Avraham had were automatically referred to as Pilagshim.
Ha'amek Davar: The custom was that a man drew close his children from his esteemed wife, and distanced his children from concubines, and they would not inherit 1 - even though this clashes with Torah law. And that explains why the B?nei Keturah are called ?B?nei Pilagshim?, even though she was not really a Pilegesh. 2
Ha?amek Davar: Like we find by Yiftach. See Shoftim 11:1-2.
Ha?amek Davar: In the same way as the ?B?nei ha'Nevi'im? were not sons of Nevi'im.
Bearing in mind the previous Pasuk (25:5), which says that he gave everything to Yitzchak, what sort of 'gifts' did Avraham give the sons of the Pilagshim?
Rashi #1: The name of Tum'ah. 1
Rashi #2: All the gifts that he received on behalf of Sarah as well as all the other gifts that were given to him. 2 Everything that he earned by the toil of his hands, he gave to Yitzchak.
Targum Yonasan: He gave them property and moveable goods - now, in his lifetime.
Rashbam: He gave them much money (in addition to what they would inherit in Avraham's place of origin - refer to 25:6:6:1).
It says "Nasan" (he had 3 given) to Bnei ha'Pilagshim, i.e. before he sent them away. Va'Yiten (he gave, i.e. now) all that he had [left] to Yitzchak. (PF)
Michtav me'Eliyahu (Vol. 5, p. 462; from the Zohar): He gave to them Chochmah of this world. This was Chochmas Bnei Kedem (Melachim 1:5:10).
Refer to 25:6:153 and the note there. Gur Aryeh - Why doesn't Rashi explain simply that he gave valuables? Avraham had already given all that he owned to Yitzchak (25:5).
From which he did not want to benefit - based no doubt, on the Pasuk "v'Sonei Matanos Yichyeh" (Mishlei 15:27). Keli Yakar - what he did not work for is not called "Asher Lo."
What is the definition of a 'Pilegesh'?
Rashi: A woman who is married (with Kidushin), but who lives with her husband without a Kesubah. 1
Ramban: A woman who lives with a man without Kidushin.
Why does the Torah add the words "be?Odenu Chai"?
Seforno: Because Avraham did not want to rely on any of the various ways of bequeathing after his death.
Why did Avraham send the B?nei Keturah to 'the land of the east'?
Rashbam: To take over the lands that he inherited there 1 from his family.
Chizkuni, Malbim and Ha'amek Davar #1: It was lest they argue with Yitzchak over the inheritance of Eretz Yisrael. 2
Ha'amek Davar #2: He sent them east of the east land, to distance them from worshippers of the sun and nature. In Kedem, they used witchcraft to overcome nature. Bnei Noach are not commanded about witchcraft. Even the opinion that disagrees, he agrees that it is not as severe as idolatry.
Chizkuni: In Aram.
Malbim - even though he did not send away Yishmael (Yishmael helped bury Avraham), Yishmael saw that he dispelled the B?nei Keturah, and he realized that he has no more rights than they do. Ha'amek Davar - there was more concern for the B?nei Keturah, lest they say that "be'Yitzchak Yikarei l?cha Zara" excludes only Yishmael, who was already born. Also, Yishmael's mother was a Shifchah, so he is not considered a son compared to Yitzchak. Or ha'Chayim, in 16:5: Yitzchak owns Yishmael, the Peiros of his mother's Shifchah.
The Torah does not mention the Bnei ha'Pilagshim again. What happened to them?
Michtav me'Eliyahu (Vol. 5, p. 461): They separated from Kedushah and joined to the other nations. However, Avraham cast many sparks of Kedushah into Yishmael and Bnei Keturah, and Yitzchak into Esav. Yisrael needed them - to afflict us when needed, or that we should learn from their afflictions - "Hichrati Goyim... Tikchi Musar" (Tzefanyah 3: 6,7).
QUESTIONS ON RASHI
Rashi writes: "Avraham gave gifts - He gave over to them the names of impurity." Rashi (to Sanhedrin 91a) explains this to mean acts of demons and sorcery. But sorcery would later be forbidden to Bnei Yisrael; would Avraham allow his sons to practice it?
Gur Aryeh: He gave them the means to escape sorcery that had been used against them, or to free a person from a demon that had taken hold of him. Additionally, it might be permitted to inquire of or adjure a demon.
Rashi writes: "A wife (Ishah) has a Kesuvah; whereas a concubine (Pilegesh) lacks a Kesuvah." Ramban asks - The Kesuvah is a Rabbinical enactment?
Gur Aryeh: As Ramban writes, the correct Girsa (in Sanhedrin 21a) is that a concubine has neither Kidushin nor a Kesuvah. It is difficult to explain as Rashi does. A monetary obligation can be forgiven; if one was Mekadesh a woman on condition that he not owe her a Kesuvah, would she be a Pilegesh? 1
I.e. it would not show a deficiency in the marital status itself.
Rashi writes: "[The word ha'Pilagshim] is written without a 'Yud,' to teach that there was only one concubine." If so, there should be no Mem (which is the suffix that usually indicates the plural)!
Peninim mi'Shulchan ha'Gra: A man may not keep a wife without a Kesuvah. Why is it not called a Kesav? There is a Yud in Ish, and a Hei in Ishah. Vav and Hei were put into the word Kesuvah, to complete HaSh-m's Name. Rashi said that a Pilegesh has no Kesuvah. Without the Yud, we read Palag Shem, i.e. only half of HaSh-m's Name is there. (In a true marriage with a Kesuvah, His full Name is there.)
Gur Aryeh: The verse means, all of these were concubines' sons, among the many concubines in general. 1
I.e. the plural is not referring to Avraham's concubines specifically; for he had only one. (EK)
Rashi writes that Avraham gave the Shem Tum'ah to the Bnei ha'Pilagshim. What is this?
Chizkuni #1: It is a name of HaSh-m that they can say even when Tamei, in order to impose oaths on Shedim. 1
Chizkuni #2: It is a name (not of HaSh-m) that they can say to impose oaths on Shedim.
Malbim: He knew that they will be under Mazal and stars, and gave them names to rule over them. This is not proper to keep, rather, to give to others.
Chizkuni: Some reject this. Heaven forbid, Avraham would not give a Kadosh name to Resha'im! (What is the source that they were Resha'im?) (PF)