Every time we question if this is what we are supposed to be doing, God reminds us that this is it. For example, a young girl came up to me and said, "Two weeks ago I was going to take my life and I was praying that God would show me a sign that He loved me. I turned on the radio station and heard 'After the world is no more'," which is a song about how God has loved us from the beginning and how He will love us forever. After she heard the song, she decided she wanted to live and instantly gave her live to Christ. After hearing something like that, you know God is using you and that you are here for a purpose.