I used to make fun of shirts like this, including those that wore them. "World peace is impossible!", I would say and I would use scripture to back up my runaway mouth. "Not until Jesus comes back so why even bother!", was once my motto. Such a shameful way of thinking.
A very dear friend of mine gave this shirt to me. While he was not the only one that helped reshape my views on this particular topic, he was one of the more influential. Now I wear it anywhere. I enjoy the looks I get and the comments.
You see, just because I still believe that absolute peace will not reign on this earth until Christ comes back, that does not mean I should not be working every day towards peace. I am not out gallivanting across the globe trying to mend nations, but each day I walk through my little part of the world, I can focus on bringing peace to those around me and myself.
I am called to. I am called to love, be kind and gentle to those around me. I am called to exercise the very peace I know will come later, in my daily routine. The fact that absolute peace can not exist right now, does not give me the out to live without peace or to ruin the peace I find in others.
You throw a pebble in a pond. This creates a ripple. A small little pebble can change a surface area much larger than itself, with each ripple growing larger and multiplying in effect. You don't have to worry about changing the world, focus on those around you. Show them peace, love and grace. You do this, and it will multiply.
I may not be able to bring about world peace, but I can work to make peace in my world.