Matthew describes an incredible event which took place during Christ's death: From noon on, darkness came over the whole land until three in the afternoon (Mt 27.45). To me it is interesting to note the parallel between the darkness at Jesus' crucifixion outside of the city (cf. Mt 27.32; Heb 13.12) and the description of the damned at the judgment as being thrown into an outer darkness (e.g., Mt 25.30). The parallel suggests that Jesus is here suffering or undergoing that eschatological punishment to which unrepentant sinners will be condemned at the judgment.
If Jesus' state is any indication of what the judgment will be like, we can know that it is a terrible place to be avoided at all costs. It is violent, dark, and demonic, through and through. Imagine what an evil, wintry heart can look upon a man in his dying hours and mock him! As the light of life is being snuffed out, as the weakly flickering flame of his soul's candle struggles at its breaking point, you throw his entire life in his face and declare him a fraud, a deceiver, a weakling. That kind of bitter disregard, contempt, hate -- that is what the outer darkness will be like. It makes perfect sense, then, that Christ would say it's better to cut off your limbs than enter into Gehenna whole (Mt 5.29-30).
I wish to make a further argument at this juncture. Christ evidently suffers the eschatological judgment of God, and yet he still resurrects unto glory. To my mind this undermines the necessity that hell be (chronologically) eternal. After all, if Christ undergoes the eschatological judgment for sin, as there is plenty of evidence here to suggest, and yet he can come out "on the other side," so to speak, who is to say that this could not be true for everyone? In fact we may come to the conclusion that Christ's death has transformed hell and the judgment itself: through his death, he has changed the quality of hell, so that by his resurrection he guarantees the escape of all.
Some persons may think that this compromises the reasoning to avoid hell: if hell isn't literally forever, why bother avoiding sin? After all I'm going to get out eventually, no matter how "bad" it may be in the meantime, right?
The problem is that no one actually thinks like this except when attempting to argue against universalism. Say you had to take a plane to get from Phoenix to Seattle, and you had two options: the first flight will arrive without much trouble, and will actually be quite pleasant; the second flight will be greatly delayed, will crash somewhere in the Grand Canyon, and you will be forced to climb out -- the elements and the animal kingdom simultaneously working against you, your life in peril the entire time -- and trek through miles and miles of desert to get to the Las Vegas airport; the flight from Vegas, too, will crash somewhere in the middle of nowhere, and in general the entire trip (which will have lasted much longer than necessary or desirable) will be incredibly arduous from the start. No one in their right mind thinks it's really no different to choose the second rather than the first. No one, except in being intentionally perverse, could think that ultimately one is not be preferred to the other.
The only difference is that the two-flights scenario is nothing like what hell will be. Christ himself, knowing even about his own resurrection, nevertheless prays to his Father that things be done differently if possible (Mt 26.39). Even Christ himself wanted to avoid the cross, wanted to avoid the hell of God's judgment, despite the fact that he knew this is what he had come for, and that he would be resurrected on the third day. This is proof positive that the temporal finitude of God's judgment does not compromise the deterrent power of God's judgment. Hell is -- well, hell, and so you ought to avoid by all costs. It will literally be the death of you if you end there.