Apart from our willingness, we should have commitment to our calling from God. We used Isaiah 6 last time to illustrate willingness and its importance; we can use it as well for commitment. In this call from God, Isaiah responds to God's call with "Here I am, send me," and no sooner does he say this than he begins to hear just what a tough job he was being called to. It was his willingness to commit to a tough task that he nonetheless went forward with his Yes. In my morning devotional reading of Philippians 4, in verse 3 "Yes, and I ask you also, my loyal companion, help these women, for they have struggled beside me in the work of the gospel, together with Clement and the rest of my co-workers, whose names are in the book of life," I read the word "struggled beside me in the work of the gospel." We know Paul's story. We know that he still said Yes even after Christ revealed to him all that he would suffer. But Paul also understood that because of his willingness and his commitment to continue forward, listening and obeying Christ, he too would receive a great prize, indicated by the closing of that verse three, "whose names are in the book of life."
It's not always easy and yes, we sometimes think of exit routes and plans from this call to ministry; but our commitment should keep us moving obediently and faithfully forward. That faithfulness will bring Christ fruit.