I remember returning from vacation and having to preach the next day. I wasn't quite ready. My down time during my vacation didn't quite go as planned, and I was feeling really unprepared. I felt so unworthy (not that I ever feel worthy of the call to preach) of standing in the pulpit and delivering a message that I felt needed some more time to develop. I was tempted to pull out an old sermon and preach it. In my conversation with the Lord, I expressed those feelings. Then I heard the Lord speak to me, and this is what He said; "I did not choose you because you were worthy. I did not call you because you had it all together. I called you for my purpose. Even when you were dead in trespasses and sins, I loved you and called you to preach my Word." It was one of the most powerful sermons, I have preached.
I express this today, in the hope of helping someone who may be feeling unworthy to carry out the task or responsibility that God has called and chosen you to do. Remember, He chose you. Not the other way around.
Blessings!