1 Corinthians 9:25

Every athlete exercises self-control in all things. They do it to receive a perishable wreath, but we an imperishable. 

1 Corinthians 9:25 (ESV)

In this verse Paul continues the metaphor of the athlete. Here, he is likening self-control of an athlete to the determination of a follower of Christ to make disciples. When we are at the end of our lives, those we helped lead to Christ will be the imperishable prize. They will be in heaven with us for eternity. Anything else we choose to focus on in this life will be just like the wreaths athletes gain, quick to perish.
With my eyes set on eternity, it becomes a lot easier to handle the difficult things of this world. For me, making disciples can be a very uncomfortable process. Many already have their walls up when the name "Jesus" is mentioned or they are clinging to their own religious traditions so tightly they can't see God's grace. One of the classes in training is called Speaking the Word. We were all given different made-up circumstances in which we had 1 to 3 minutes to convey the Gospel message to the classmate next to us. I had to pretend to share with a women as I was waiting for the light to change at a crosswalk. While the situation wasn't real, it was still very difficult! I'm so grateful that when these kinds of opportunities really do arise, I have the promise of that person's salvation to encourage me through the hard times. This imperishable wreath at the end of everything makes it all worth it.