בְּיוֹם֙ עֲמָֽדְךָ֣ מִנֶּ֔גֶד בְּי֛וֹם שְׁב֥וֹת זָרִ֖ים חֵיל֑וֹ וְנָכְרִ֞ים בָּ֣אוּ שערו [שְׁעָרָ֗יו] וְעַל־יְרוּשָׁלִַ֙ם֙ יַדּ֣וּ גוֹרָ֔ל גַּם־אַתָּ֖ה כְּאַחַ֥ד מֵהֶֽם׃
當外人擄掠他的財物、外邦人進入他的城門、為耶路撒冷拈鬮的那日，你袖手旁觀，站在一旁；你也如同他們中的一個。
Rashi
you, too, are like one of them—I account it for you as though you were one of their attackers.
Tze'enah Ure'enah
“On the day that you stood aside, on the day when foreigners carried off” [1:11]. When the evil Titus came against Israel and Jerusalem, Edom rejoiced and also stood on the side to insult Israel and gave Israel into the hands of the people from the city of Rome. You Edom should have helped Israel, since they are your brothers. The Holy One had forbidden in the desert, with Moses our Teacher, that Israel should not do any evil acts to Edom because they are your brothers. During the destruction of Jerusalem, Edom did not think about this brotherhood.6Radak, Obadiah, 1:11.