The word ministry defines the spiritual service. It can be implied as the anointing or imparting of the Spirit or the creating of sacred moments.
Although the Heavenly Father has declared originally that all followers are priests and priestesses by divine birthright, certain persons are called specifically for such a work in communities.
There are those that have been trained and tested academically to be truly prepared and capable to serve and assist the poor and the many for a redemptive work in communities.
So ministry as a spiritual service is ultimately that labor for communities, rather than simply laymen individuals which impart the anointing of Spirit.