A recent post on Andy Goodliff's blog on starting in ministry attracted a comment from me. I've re-posted the comment below.
The blog was on how seminary study does not equip one for the real world of 'ministry'.
My comment, a little edited:
Being a 'minister' in organised church terms is very much a craft, which suggests that becoming a minister should be by an apprenticeship. That is, fresh out of theol. college, you are not a minister (although you might have the title), but have a body of knowledge and a level of intellectual understanding (but not necessarily wisdom or applied love) that will assist you be a minister, but not make you one. I don't think that it's even a precondition.
Step one would be to serve in a church under the guidance of its elders; later you might become an elder too, if the Spirit so provides.
However, a highly trained person might make a great teacher: different from the omnibus role we have today of professional minister (I note the unbiblical game was given away by the term 'laity', incidentally).
It would be great, I think if all Christians underwent some form of formal Christian education: some may do short courses, others might do PhDs (and then not advertise the fact out of properly placed humility :-) ); some would then go on to be Sunday School teachers, convene youth or adult study and prayer groups, others would assist with the formal weekly gatherings (aka services) as moderator, reader, speaker, teacher, prayer, etc.
This would tend to create ministering communities, rather than one-man shows, and one would hope, such communities that could organically support their ministry needs, without 'flying in' experts who are not part of the community to get rapidly grafted on, with many attendant problems (but some benefits, too, I agree).
It is the professionalisation of Christian ministry that is a problem. Once people are denied a valid voice in their Christian group, because they must defer to an expert (how does one become an expert in Christian life, or living in a loving manner against the challenges of every day?) they are told, implicitly, that they have no voice that's worthwhile for evangelism, or any other spiritual purpose; which is Not Good!