Unconditional love rooted in essence

ויאהב יצחק א"ע כי ציד בפיו.

"And Yitzchak loved Esav, for game was in his mouth" (Bereishis 25:28).

The Sefas Emes examines why the Torah specifies the reason for Yitzchak's love of Esav.

הכתוב נותן טעם כי לא הי' אהבה אמיתית רק תלוי' בדבר לכן בטלה דבר בטלה אהבה.

The verse gives a reason, for it was not a true love but one dependent on a thing; therefore when the thing ceased, the love ceased.

By stating a cause ("for game was in his mouth"), the Torah signals this was ahavah she'teluyah b'davar — love contingent on something — which, like the Mishnah in Avos teaches, ends when its cause ends.

ולכן כשהקדימו יעקב בצידה אבדה האהבה.

Therefore, when Yaakov preceded him with the "game" (the food he brought), the love was lost.

Once Yaakov supplied the very thing the love depended on, the basis for Yitzchak's particular love of Esav fell away.

אבל רבקה אוהבת א"י בלי טעם ונתקיימה האהבה לעד.

But Rivkah loved Yaakov without a reason, and the love endured forever.

Rivkah's love for Yaakov rested on no external cause, so it was a love that lasts permanently.

וכן כוונת המדרש במ"ש כל שהי' שומעת קולו היתה מוספת אהבה.

And this is also the intent of the Midrash that says, "whenever she heard his voice, her love increased."

The Midrash that Rivkah's love grew each time she heard Yaakov's voice underscores that it had no fixed external cause.

פי' שלא הי' תלוי' בדבר.

That is, it was not dependent on any thing.

A love that only deepens is precisely one not bound to a single condition that could lapse.

וכן אהבת המקום ב"ה לבנ"י ג"כ אינה תלוי' בדבר אף לא במעשיהם.

And likewise the love of the Omnipresent, blessed be He, for Bnei Yisrael is also not dependent on any thing — not even on their deeds.

Hashem's love for Bnei Yisrael is unconditional, resting not even on their actions.

רק בחר לו חלק ה' עמו כמ"ש עליו עשיר ישמח בחלקו.

Rather, "the portion of Hashem is His people" — He chose for Himself, as it is said of Him, "a rich man rejoices in his portion."

Bnei Yisrael are Hashem's own chosen "portion" (Devarim 32:9); He rejoices in them as one rejoices in what is intrinsically his, regardless of any condition.

וז"ש אהבתי אתכם ואמרתם במה אהבתנו הלא אח עשו ליעקב כו' פי' שאין טעם במה לתלות האהבה רק שבנ"י מדובקין אליו ית' בשורשם:

And this is "I have loved you, and you said, 'In what have You loved us?' — Was not Esav a brother to Yaakov?" (Malachi 1:2) — meaning that there is no reason on which to hang the love, only that Bnei Yisrael are bound to Him, may He be blessed, in their root.

When Bnei Yisrael ask "in what" Hashem loves them, the answer is that there is no "in what" — no external cause — for the love flows from their very root being attached to Him.

Summary: Yitzchak's love of Esav was "dependent on a thing" (the game in his mouth) and so it ceased; Rivkah's love of Yaakov rested on nothing external and endured forever. So too Hashem's love for Bnei Yisrael depends on no condition, not even their deeds — they are His chosen "portion," bound to Him at their very root. That is why, to "in what have You loved us?", the answer is that the love has no cause to which it can be tied.