There is a difference between being a good person and having a ministry. 

I have lots of good people who attend the Church I lead.  They worship with us occasionally, and then during their week, they help people and are friendly to others as the opportunity presents itself.  They have no exact strategy to make sure they are continually helping others, but they are available if needed.  They may not mention Jesus, but they feel their actions reflect him, and that is enough.  These individuals smile and are genuinely good people.

A ministry can happen anywhere, but it always requires routines and a plan.  There are regularly scheduled times where something will happen for the kingdom of God.  Someone will be fed, clothed, taught, visited, invited, encouraged, and a host of other things.  In the end, it is clear that this activity was done because Jesus is Lord and wants us to make a difference in his name.  Ministry has a cumulative impact on individuals, Churches, and communities.  These people are also good, but they work within a system for the greatest impact possible. 

Don’t get me wrong; I want everyone to be the good person God desires us to be as we follow Jesus.  But people who make a real, lasting difference have a ministry.