ציטירנדיקער פּירוש אויף אסתר 6:12

Another explanation: He was occupied with his sack-cloth... Rashi deduces this because it is written here, “Reuvein returned to the pit,” and it says, “Mordechai returned to the king’s gate wearing sack-cloth” (Esther 6:12). Just as “returned” over there refers to sack-cloth and fasting, so too here. Reuvein must have done his repentance secretly, and thus he was absent at the time of Yoseif’s sale. Otherwise it would contradict Rashi’s explanation of וזאת ליהודה (Devarim 33:7), that Yehudah’s confession over the incident with Tamar was what influenced Reuvein to confess and repent over the incident with Bilhah. Therefore it must be that Reuvein first repented secretly and later he did so publicly.

[Daniel 2:49] v'Daniel bitraʿ malka (וְדָנִיֵּאל בִּתְרַע מַלְכָּא - And Daniel was at the king’s court [lit. gate]): For this is a great status (maʿalah gedolah - מַעֲלָה גְדוֹלָה), because there sat the judges (ha-dayyanin - הַדַּיָּנִין) and the magistrates (v'ha-shoftim - וְהַשֹּׁפְטִים). And likewise: “and Mordecai was sitting at the king’s gate” [Esther 2:19, Esther 2:21; Esther 5:9, Esther 5:13; Esther 6:10, Esther 6:12], as I explained in [my commentary on] the Scroll of Esther.