"The LORD said to him, 'Who gave man his mouth? Who makes him deaf and mute? Who gives him sight or makes him blind? Is it not I, the LORD? Now go; I will help you speak and will teach you what to say.' But Moses said, 'O LORD, please send someone else to do it.'"
Moses is running low on excuses. Despite God's constant reassurance that He will take care of everything, Moses comes up with reason after reason and fear after fear in hopes that he can get out of what God is asking him to do until finally he just outright says it, "O LORD, please send someone else to do it."
God is sovereign in all our lives and has a calling for each and every single one of us, but often we put it off. "God, I need to get my degree before I can serve you." "God, I need to save up money first before I can do that." "God, I am not very good at evangelism!" Believe me, I'm sure God has heard every single excuse in the book why you aren't doing what he asked of you to do and God asks of us the simplest things! He even promises to equip us adequately for the mission if we just go, and we sit and make excuses.
Maybe you don't know God's will for your life, but are you trying to figure it out? Come on: What's your excuse?