Deuteronomy 29:29 says "The Lord our God has secrets known to no one. We are not accountable for them, but we and our children are accountable forever for all that he has revealed to us, so that we may obey all the terms of these instructions."
This is such a great reminder! God sees the bigger picture of our lives, we don't. A good friend of mine uses the example of a puzzle. We get puzzle pieces through out life and sometimes we can't make sense of them but that's because only God sees the ultimate picture.
So don't worry so much about the bigger picture. Just handle one puzzle piece at a time. Obey Him and be patient - God will show you His beautiful puzzle top in HIS TIMING =]