"But I know that the king of Egypt will not let you go unless compelled by a mighty hand. So I will stretch out my hand and strike Egypt with all the wonders that I will do in it." - Exodus 3:19-20, ESV
"Are you sure, God?"
"Are you crazy, God? Do you know how many things could happen if...?"
Have you been there? Have you been at that point with Jesus where he has laid something on your heart to do but you're just not sure how he can make it a reality? So you get scared. You get worried and anxious. You ask for confirmation (and according to Exodus 3, God anticipates that confirmation is needed). And realize: I'm right there with you.
In Exodus 3:19-20, I'm reminded of the fact that God knows the actual problems that will come up. He actually knows the obstacles that we will face, but he also has the key to the remedies. Be encouraged. Be reminded. The obstacles are already worked out in the timeline of God. What could happen is not in the reality of God's existence. "Could" is not in God's plan. "What is" is all that is.