Jerry Seinfeld once noted that most people's number one fear is public speaking. Number two is death. This means that the average funeral attendee would feel more comfortable being the person in the casket than the person delivering the eulogy.
Moses would have preferred the casket. In Exodus 4:10, he cries out to God, "I am not eloquent, either in the past or since you have spoken to your servant, but I am slow of speech and of tongue." There's something familiar to me in Moses' words. I've heard many people tell God what they can't do, but I've also witnessed what happens when they overcome that fear and serve anyway. I've listened to amazing messages from people who told me they couldn't speak, heard heartfelt prayers from those who told me they couldn't pray out loud, and seen God's grace poured out on those who simply said "yes" to him.
Before we tell God what we can't do, we should take note of what he can do through us—any of us. That's what God confronts in Moses before he leaves the burning bush. If we listen carefully, we can hear his call for us and his promises as well.