Looking at Bereshit/Genesis 25:22
Some commentators [based on the Midrash of Genesis Rabbah 63:6] offer a explanation [of “Vayitrotzatzu: and they struggled”] as having the meaning of “ratz/rutz: running.” When Rivkah would pass by a place of Torah study (Beit Knesset, Tefillah, Midrash) [of Shem and Ever], Ya'akov would run and push to come out. When she would pass by a place of an idol worship or wordly place, Esav would run and push to come out.
Rashi presents another explanation in which the two boys fought over two worlds (Olam Hazeh and the Olam Habah).
It seems those kind of commentaries present a twofold: one side (spiritual) v.s. another side (earthly) represented in the characters, running and the two worlds.
What I would like to know though is why then the two boys fought over both worlds?