It's A Matter of Faith - Philippians 1:6

If we can trust that the people who make a puzzle have put every piece in the box to complete the puzzle then why can't we trust that God has placed every piece that is needed in us to accomplish His good and perfect will for our lives? It's a matter of faith and trust in the Creator. 

Philippians 1:6 (NLT)
"And I am certain that God, who began the good work within you, will continue his work until it is finally finished on the day when Christ Jesus returns."