Lech Lecha details Avram, Sarai, and Lot’s travels to Canaan, the famine that forces them to Egypt, and their journey back to Canaan. Their trip produced wealth in the form of flocks and cattle and led to Avram and Lot’s herdsmen bickering. To prevent future conflict, Avram asked Lot to pick a direction where he wanted to go, and “if you go left, I will right, and if you go right, I will left” (13:9). Onkelos translates that Avram will go in the opposite direction of whichever direction Lot chooses.
Rashi offers an alternative explanation, one that makes sense in the context of future events. Rashi explains that Avram suggested that if Lot veers left, Avram will veer to the right, and vice versa. The nuance is that veering is not far; it is still close enough to stand by Lot to help and protect him, which Avram ended up doing several times. Rabbi Chaim Marder solidifies this thought, explaining that even though they could not live together, Avram and Lot were still family, and Avram felt responsible for being always available for his family. This sentiment is a beautiful behavior model for all, one of unconditional love and acceptance, despite disparities that may exist.