What does the Navi say about "Leshon Limudim"?
Rashi: Hashem sent me, and gave to me a tongue proper to teach, in order to know how "to support the weary and thirsty to hear Hashem's words."
Radak: The Nevi'im said about himself that Hashem gave to him Leshon (ability to speak) like people normally speak. Limudim is like "Limud Midbar" (Yirmeyah 2:24). "Va'Yasem Pi k'Cherev Chadah" (above, 49:2) - He prepared my mouth to speak clearly and quickly, like one who is used to speaking.
Malbim: He returns to ask why He came, and no one answers. Do not say that you did not hear Him call - He gave to me Leshon Limudim to arouse you to His service!
What is the meaning of "[Lada'as] La'us"?
Rashi citing Menachem: La'us is from the root Es - to fix for them times.
Radak: It is to know Hashem, and La'us one who is Ayef, i.e. thirsty to hear Hashem's words - "Lishtos ha'Ya'ef ba'Midbar" (Shmuel II, 16:2), i.e. thirsty. "B'Eretz Tziyah v'Ayef Bli Mayim" (Tehilim 63:2). La'us is to say a matter in its time.
What is the meaning of "Ya'ir ba'Boker ba'Boker"?
Radak #1: Perhaps his Nevu'os were at night. It is as if Hashem woke him in the morning [after] the Nevu'ah.
Radak #2: Day after day. There was no break in his Nevu'ah, to be a month or days without Nevu'ah.
Malbim: A Navi for nations must be able to speak [simply about exalted matters] always, not only at certain times.
What is the meaning of "Ya'ir Lo Ozen"?
Rashi: He will arouse my ear with His Ru'ach ha'Kodesh.
Radak: He prepared my mouth to speak and my ear to hear teachings, like it said "Nasan Li Leshon Limudim."
Malbim: A Navi for nations must speak in vision, and not in riddles. He chooses his words according to the understanding of the listeners.
What is "Lishmo'a ka'Limudim"?
Rashi: Like teachings should be - Emes and straightforward.
Malbim: I heard the Nevu'ah according to level of the Talmidim, and according to their understanding.