Zechariah 9:9
גִּילִי מְאֹד בַּת-צִיּוֹן הָרִיעִי בַּת יְרוּשָׁלִַם הִנֵּה מַלְכֵּךְ יָבוֹא לָךְ צַדִּיק וְנוֹשָׁע הוּא עָנִי וְרֹכֵב עַל-חֲמוֹר וְעַל-עַיִר בֶּן-אֲתֹנוֹת
Rejoice greatly, daughter of Zion! Shout, daughter of Jerusalem! Behold your king coming to you! He is righteous and victorious, humble and riding a donkey - a mere foal, the offspring of a donkey.
The image of a righteous, victorious and humble king riding to Jerusalem on a lowly donkey is taken by most as a messianic prophecy. The Ibn Ezra, however, attributes it to Judah Maccabee, hero of the Chanukah story. He supports this position by citing Zechariah 9:14, just a few verses later, which states that G-d will arouse the Jews against the forces of Greece, led by the sword of a mighty warrior. When the Hasmoneans started their uprising against the Greeks, they had neither money nor horses, which explains the need to ride donkeys.