A pet peive of mine is when there's a long line at the grocery store and a new cashier opens up his stand, but the people at the end of the current line get to the front. Doesn't that bug you? I say this admitting that I have taken advantage of this in the past when in a rush, and it bugs me that I did it too.
Anyways, on a laid back Satruday here in Costa Rica, I walked to the local corner store to pick up some avocados. The line was as long as I had ever seen it, and one cashier was doing the best he could to bang through it. Then there was this guy at the end of the line with me who was trying to hail another cashier to open another checkstand. As soon as the cashier opened the other line, this guys bolted and got to the front. I thought to myself, "the last got first, but I don't think this is what Jesus was talking about".
Being the last in this life really sucks. Being without a job, being without a home, being abused, being spit on, etc. is not how God envisioned for life to be. He has compassion on people who have endured such pain. Plus, these people tend to take Jesus up on his offer for another life. These two factors, God's mercy and their willingness, propel them from the back to the front. I know I'm near the front of the line, and Jesus' word about the first being last concerns me, but I smile when thinking about the justice in it all.