Have you ever played the game red light/green light when you were a kid? I hope I am not showing my age.  The rules of the game were that when a person yelled "green light", it was time to go and when they yelled "red light", it was time to stop. 

What are you doing with the green lights on your road to life, as it relates to your purpose?

Consider every green light and know it is time to move forward and not be stopped by a red light (past, mistakes, old situations, people, etc.).  

This book (The Right of Way) by J. Vanlear Woods will certainly change how you look at your life's purpose.