In my mind it is for 2 reasons, one to continually recognize our dependence on God, and secondly, because he wants us to.
The question is not why God condemns some, but rather why he saves any at all? Are we not all guilty? Is there anything in us apart from the Grace of God that deserves mercy? Justice dictates that we are guilty and should pay the price of seperation or hell. It is only through His mercy that anyone is saved. Here you and I will disagree on the existence of Hell. You cannot truly appreciate the benefits of heaven without the existence of the opposite. If you will look all of creation portrays this also, sweet tastebuds, sour tastebuds, joy, and sorrow, etc. I can appreciate enjoying the ministry of an individual, but caution against following a man, even Martin Zender. He is as fallible as all of us, and can contextually bring scriptures out to prove his point like many have done in this thread. To be honest, I have not been able to listen to the clips, my computer is messing up right now, but will be listening to them as soon as I can, it sounds like he has an interesting insight from your quotes.
Here's a good write up on Geenna and "hell."
http://www.concordant.org/expohtml/DeathAndJudgment/TheGehennaOfFire.html
THE RAVINE OF HINNOM
indent.gif (54 bytes)In popular theology, in accord with ancient tradition, it is claimed that “Gehenna” is a symbolic expression used in reference to eternal punishment. Milton also employs it thus in his familiar lines:
“The pleasant Valley of Hinnom, Tophet thence
And black Gehenna call’d, the Type of hell.”
Paradise Lost, Book One, lines 404,405
In the Scriptures, however, “Gehenna” (“hell,” AV)-all incredible myths to the contrary notwithstanding-does not speak of “the place of the eternal torments of the damned.” Instead, it refers to an actual place on earth, namely, the valley (or “ravine”) of Hinnom (Neh.11:30) in the land of Israel. The ravine of Hinnom is a valley to the southwest of Jerusalem (“the ravine of the son of Hinnom”; Joshua 15:8). The Hebrew phrase gê (“ravine of”) hinnom became geenna in Greek, whence Gehenna in Latin and English.