Is God calling you to Prison Ministry? Prison ministry is not a place of "that's good enough" warm bodies, but "hand-picked servants."
Often times God calls us to prison ministry years before it actually happens. I remember God calling me to preaching years before my training and first opportunity. Sometimes I think (I know in my case) he calls us and matures our character during the years of waiting... he puts us in places of training for future ministries. Don't waste a moment in serving where you are at - it is building upon your character for greater kingdom impact.
You did not choose me, but I chose you and appointed you. John 15:16
Do not be anxious about anything, but in everything, by prayer and petition, with thanksgiving, present your requests to God. And the peace of God, which transcends all understanding, will guard your hearts and your minds in Christ Jesus. Phil 4:6-7