17:19י״ז:י״ט
1 א

אבל. לְשׁוֹן אֲמִתַּת דְּבָרִים, וְכֵן אֲבָל אֲשֵׁמִים אֲנַחְנוּ (בראשית מ"ב), אֲבָל בֵּן אֵין לָהּ (מלכים ב ד'):

אבל VERILY — This word implies confirmation of a statement, just as (Genesis 42:21) “Verily (אבל) we are guilty”, and (2 Kings 4:14) “Verily (אבל) she has no son”.

2 ב

וקראת את שמו יצחק. עַל שֵׁם הַצְּחוֹק, וְיֵ"אֹ עַל שֵׁם הָעֲשָׂרָה נִסְיוֹנוֹת וצ' שָׁנָה שֶׁל שָׂרָה וח' יָמִים שֶׁנִּמּוֹל, וק' שָׁנָה שֶׁל אַבְרָהָם:

וקראת את שמו יצחק AND THOU SHALL CALL HIS NAME ISAAC — with reference to his laughter. Some say the name has reference to the ten (י) trials, the ninety (צ) years of Sarah’s age, the eight (ח) days of the circumcision and the hundred (ק) years of Abraham’s age (Genesis Rabbah 53:7).

3 ג

והקימתי את בריתי אתו. לָמָּה נֶאֱמַר, כְּבָר כְּתִיב וְאַתָּה אֶת בְּרִיתִי תִשְׁמֹר אַתָּה וְזַרְעֲךָ וְגוֹ'? אֶלָּא לְפִי שֶׁאוֹמֵר וַהֲקִמוֹתִי וְגוֹ', יָכוֹל בְּנֵי יִשְׁמָעֵאל וּבְנֵי קְטוּרָה בִּכְלַל הַקִּיּוּם, תַּ"לֹ וַהֲקִמֹתִי אֶת בְּרִיתִי אִתּוֹ – וְלֹא עִם אֲחֵרִים: ואת בריתי אקים את יצחק. לָמָּה נֶאֱמַר? אֶלָּא לִמֵּד שֶׁהָיָה קָדוֹשׁ מִבֶּטֶן. דָּ"אַ אָמַר רַ' אַבָּא, מִכָּאן לָמַד קַ"וָ בֶּן הַגְּבִירָה מִבֶּן הָאָמָה; כְּתִיב הִנֵּה בֵּרַכְתִּי אֹתוֹ וְהִפְרֵיתִי אֹתוֹ וְהִרְבֵּיתִי אֹתוֹ, זֶה יִשְׁמָעֵאל, וְקַ"וָ וְאֶת בְּרִיתִי אָקִים אֶת יִצְחָק:

והקמתי את בריתי AND I WILL ESTABLISH MY COVENANT WITH HIM — Why is this stated? Is it not already written (Genesis 17:9) “as for thee, thou shalt keep My Covenant, thou and thy seed etc.”? But since is said, (Genesis 17:7) and I will establish My Covenant between Me and thee and thy seed after thee in their generations”, it might be inferred that the children of Ishmael and the children of Keturah (who are all descendants of Abraham) are included in this promise of the establishment of the Covenant, therefore it states here (Genesis 17:19) “And I will establish My Covenant with him (Isaac), not with the others” (cf. Sanhedrin 59b). If so, why is there a repetition of the statement that the covenant will be established with Isaac in the words (Genesis 17:21) ואת בריתי אקים את יצחק “but My Covenant will I establish with Isaac”? But it is repeated in order to add the words אשר תלד so as to teach that he was holy from his birth (Shabbat 137b). Another explanation of why 5:21 is repeated is: R. Aba said, “from here Scripture draws a logical conclusion regarding the son of the Mistress (Sarah) from what is said regarding the son of the handmaid (Hagar): It is written (Genesis 17:20) “Behold I have blessed him and will make him fruitful”, and this refers to Ishmael: Surely then, it follows logically that “I must establish my covenant (of blessing) with Isaac also!” (Genesis Rabbah 47:5).

4 ד

ואת בריתי. בְּרִית הַמִּילָה תְּהֵא מְסוּרָה לְזַרְעוֹ שֶׁל יִצְחָק:

את בריתי [I WILL ESTABLISH] MY COVENANT — The Covenant of circumcision shall be transmitted only to the descendants of Isaac.