וַיֹּ֨אמֶר אַבְרָ֜ם אֶל־ל֗וֹט אַל־נָ֨א תְהִ֤י מְרִיבָה֙ בֵּינִ֣י וּבֵינֶ֔יךָ וּבֵ֥ין רֹעַ֖י וּבֵ֣ין רֹעֶ֑יךָ כִּֽי־אֲנָשִׁ֥ים אַחִ֖ים אֲנָֽחְנוּ׃
At sinabi ni Abram kay Lot: “Huwag nawang magkaroon ng away sa pagitan ko at sa iyo, at sa pagitan ng aking mga pastol at ng iyong mga pastol, sapagkat kami ay magkapatid.”
Rashi
אנשים אחים BROTHERS — i. e. kinsmen. The Midrashic explanation is: that they resembled each other in their facial features (Genesis Rabbah 41:6).
Sforno
ביני ובינך, in the future. When either one of them would select for his herds a certain grazing area.
Or HaChaim
אל נא תהי מריבה, Let no quarrel develop between me and you. Abraham told Lot that what had started as an argument between their respective shepherds was bound to lead to a quarrel between the two of them even though Lot claimed that he would never allow this to happen. After all, he respected his uncle too highly as the senior member of the family. The substance of the shepherds' arguments concerned the fact that Lot allowed his shepherds to graze on privately owned land, counting on G'd's promise that the land would belong to Abraham's family in the future. Seeing that Abraham had no children and was genetically unable to father children, Lot viewed himself as Abraham's heir. Abraham alluded to this by the superfluous comment that they were brothers.