וַיֶּֽאֱהַ֥ב יִצְחָ֛ק אֶת־עֵשָׂ֖ו כִּי־צַ֣יִד בְּפִ֑יו וְרִבְקָ֖ה אֹהֶ֥בֶת אֶת־יַֽעֲקֹֽב – And Isaac loved Esau because [his] game was in his mouth, but Rebecca loved Jacob.
We are told in Avot: “Any love that is dependent on something–when the thing ceases, the love also ceases. But a love that is not dependent on anything never ceases…”(5:16).
The verse above (Genesis 25:8) indicates that Isaac had a “dependent” love for Esau, namely because “his game was in his mouth” whereas Rebecca had no “dependent” love as she “loved Jacob” with no preconditions.
How then to explain these diametrically opposed loves?
The simple explanation could be that Esau symbolized physicality which always embodies some kind of dependent “ulterior” love whereas Jacob symbolized spirituality, a phenomenon that can exist within a pure and unconditional state.