[Gehenna Says:]

For He satisfied the yearning soul,

and filled the hungry soul with good.

(Tehillim 107:9)

The soul of man longs for infinite spirutal delights and rewards of the Olam Habah. When the days of man are over, and to be welcomed to the bliss of Gan Eden above, the blemished soul must be purged and purified in Gehenna.  Gehenna prepares the soul for the spiritual splendor that awaits it.
[-Rabbi Scherman, Perek Shira]