וַיֵּשְׁב֣וּ לְפָנָ֔יו הַבְּכֹר֙ כִּבְכֹ֣רָת֔וֹ וְהַצָּעִ֖יר כִּצְעִרָת֑וֹ וַיִּתְמְה֥וּ הָאֲנָשִׁ֖ים אִ֥ישׁ אֶל־רֵעֵֽהוּ׃
他們在約瑟面前就座，長子按著長子的名分，幼子按著幼子的次序；這些人就彼此驚奇。
Rashi
הבכור כבכרתו THE FIRST-BORN ACCORDING TO HIS BIRTHRIGHT — He struck the goblet and called aloud: Reuben, Simeon, Levi, Judah, Issachar and Zebulon, sons of one mother, take your seats at the table in this order which is the order in which you were born — and similarly in the case of them all. When he reached Benjamin’s name he said, “This one has no mother and I have no mother — let him sit beside me” (Genesis Rabbah 92:5).
Rashbam
וישבו לפניו, Joseph had given instructions to arrange the seating order in order of their birth.
Radak
וישבו לפניו, in the order in which Joseph had given instructions to seat them.