مثقال خیر و شر

Don't stop doing Khair (good). 

Therefore, perform every deed to the end  until you reach Paradise.  For example,  you have performed an act to the stage of Noon ( the act is quit obvious) but you have not completed until Asr ( result).  

In this logic every act had a continuum of preconditions until it reaches to the conclusion. 

The reason for these issues was:

 فمن یعمل مثقال ذره خیره یره

Perform any Khair (good deed) at its time,  observing the limit of time itself is (Khair). If you want to perform an act,  do it in continuum of time.