How God chooses to use you is up to Him, but if you desire to be used by Him, you must make the choice to be a part of what He is doing.
Walking into the unknown is scary; but when you think about it, living your whole life crawling around in the “dung” in the bat cave is much more scary.
Disobedience to God is never a good thing, but sometimes it turns out to be a terrible thing that changes your life forever. http://who-god-is.com/disobedience-to-god-can-be-an-awful-thing
Satan will always desire to fill your thinking with false knowledge and he always wants you to be ignorant of the truth when it comes to making major decisions. http://who-god-is.com/beware-of-false-knowledge-it-is-more-dangerous-than-ignorance
We Christians need to show a WORLD IN GREAT NEED that God is meeting OUR needs, working in OUR lives in a supernatural way, and doing "impossible" things on a regular basis in OUR lives. It is only then that a world in such desperate need will start to let OUR God become THEIR GOD!
God tells you this for a reason - to keep you strong and in the best of physical, mental, and spiritual health. I found out the hard way that constant anxiety for an extended period of time does affect you negatively in just about every way. God is capable of handling any problem, not matter how large or small. But you must make the decision to allow Him to handle it.
God desires to make a tremendous thing of your life, so He sends adversity to grow and mature you as a Christian. This makes you either run to Him or run away from Him and try to handle things yourself.
Act out of who you are, not what you feel. The Holy Spirit wants to mature you to the point that your feelings don't control how you act. You make the choice to act based on the wisdom you already have, and you immediately pray for specific wisdom to handle this situation in a way that is pleasing to God.