The prophet is not a mouthpiece, but a person; not an instrument, but a partner, an associate of God. Emotional detachment would be understandable only if there were a command which required the suppression of emotion, forbidding one to serve God "with all your heart, with all your soul, with all your might." God, we are told, asks not only for "works," for action, but above all for love, awe, and fear. ... You will seeke Me and find Me, when you seek Me with all your heart" (Jer. 29:13).This makes me think of the famous words of one of the most human of all prophets, Jeremiah. It is a personal experience which fully requires the participation of the prophet.
Abraham Heschel, The Prophets
You duped me, O LORD, and I let myself be duped;
you were too strong for me, and you triumphed. ...
I say to myself, I will not mention him,
I will speak in his name no more.
But then it becomes like fire burning in my heart,
imprisoned in my bones;
I grow weary holding it in, I cannot endure it.
(Jer. 20:7, 9)