מדרש אויף תהילים 48:6

For the kings assembled and passed by, when it was destroyed. As it is said, "Many nations have passed over this city" (Jeremiah 22:8), they passed over it and marveled. Therefore, it is said, "They will see and be astounded" (Psalm 48:6), and they will say, "Why did God do so?"...

“Behold, the kings convened, passed together” (Psalms 48:5). “Behold the kings” – this is Judah and Joseph. “Passed [avru] together” – this one became filled with fury [evra] against that one, and that one became filled with fury against this one.⁸Joseph and Judah became angry with one another. “They saw it and were astonished” (Psalms 48:6) – “The men wondered to one another” (Genesis 43:33). “They were terrified; they hastened” (Psalms 48:6) – “[Joseph said to his brothers: I am Joseph; does my father still live?] And his brothers could not [answer him because they were alarmed before him]” (Genesis 45:3). “A fearful trembling seized them there” (Psalms 45:6) – these are the tribes. They said: ‘Kings are contending with one another; of what concern is it to us?⁹The other brothers felt it was not their place to intervene in the confrontation between Joseph and Judah. It is appropriate for a king to contend with a king.’
“Judah approached him” – “One approaches another” (Job 41:8) – this is Judah and Joseph. “Not even a breath comes between them” (Job 41:8) – these are the tribes. They said: ‘Kings are contending with one another; of what concern is it to us?’