וּבְנֵ֣י צִיּ֗וֹן גִּ֤ילוּ וְשִׂמְחוּ֙ בַּיהוָ֣ה אֱלֹֽהֵיכֶ֔ם כִּֽי־נָתַ֥ן לָכֶ֛ם אֶת־הַמּוֹרֶ֖ה לִצְדָקָ֑ה וַיּ֣וֹרֶד לָכֶ֗ם גֶּ֛שֶׁם מוֹרֶ֥ה וּמַלְק֖וֹשׁ בָּרִאשֽׁוֹן׃
Be glad then, ye children of Zion, and rejoice in the LORD your God; For He giveth you the former rain in just measure, And He causeth to come down for you the rain, the former rain and the latter rain, at the first.
Rashi on Joel
the teacher for justification Heb. מוֹרֶה. Your prophets who teach you to return to Me, in order to justify you.
Ibn Ezra on Joel
And the children: Yefet [ben Ali] said that the instructor (hamoreh) is the prophet that instructs them about the righteous path. And that is why good is coming to them. And it mentioned early rain (moreh) and late rain, as [in] (Judges 15:16), "With the jaw of an ass (chamor), mass (chamor) upon mass"...
Rashi on Joel
the early rain and the late rain. Heb. מוֹרֶה, like (Deut. 11:14) “the early rain (יוֹרֶה) and the late rain (וּמַלְקוֹֹש).”