What is the significance of a Kesil emitting all his Ru'ach?
Malbim: Ru'ach is the power that puts images on the heart. Most of man's images are evil, e.g. of pride, envy, vengeance
What is the meaning of "v'Chacham b'Achor Yeshabechenah"?
Rashi: When a Kesil emits all his Ru'ach, a Chacham comes and lowers him via his answer. This is like "Mashbi'ach She'on Yamim", "Galav Atah Teshabechem" (Tehilim 65:8, 89:10).
Malbim: A Chacham conducts according to the laws of Chachmah. He rules over his Ru'ach, and does not let it rise above the depth of the Nefesh and elevate over the heart. Rather, he lowers the Ru'ach to in back of the Nefesh. The Ru'ach storms to rise over the Nefesh and eye of the heart; he forces it to remain below, in back of the Nefesh, and not appear in front of it. Via the laws of Chachmah, he learns to suppress bad images from coming on the heart, and to remain hidden in the depth of the Nefesh below.
