I don’t think that the difference is in what either can do, but how either are called to live.
A religious man or woman is avowed to live according to a rule of life, to give his life to the service of the whole Church through and with their community. Certainly a single or married person can do the same, but the breadth of their service is different, because of the needs of those being serviced.
While a brother or a nun may be called to serve others anywhere in the world or to be trained in special skills in order to serve the apostolate of their order, a single person may be restricted to offer only what he or she has to his or her local community. A married couple, on the other hand, serves primarily their children and family through nurturing and support.
As a matter of fact, monasticism came into being exactly because people were called to serve others as single people. It quickly became clear that if several banded together they could do more than by themselves, not only with regards to serving others, but also in individual spiritual growth. After all, Jesus commanded to love God and love
one another.
So, although the charisms and graces are different to live these vocations, they vary in scope, breadth and depth, but all contribute to
nurturing the body of Christ.
