I was looking into the definition of "laity" and got to thinking about how meanings of words change over the years. The original Greek simply meant 'all of the people.' I'm no scholar so I won't pretend to know if this word was even used in New Testament writings or had any Christian meaning whatsoever. I don't know when the term even entered the Church or in what context it was originally used.
I do know that the term 'laity' and its derivative 'laymen' are used quite extensively in the Church today. I do wonder if the 'religious' context and the modern cultural context differ.
From my view from the pew (i.e., my opinion) I think that we in the Church have adopted have adopted the cultural definition, namely that the laity are untrained amateurs and that the clergy are the trained professionals. This is nutty considering that my denomination prides itself on 'solo scriptura.' From my reading of the NT, this definition and 'solo scriptura' don't coincide.
According to the Epistles, we are all ministers of reconcilliation and all have gifts for the building of the Church. With the modern definition, only the professionals do real 'ministry' and the laity confines is ministry to the 'non-spiritual' aspects of ministry. Gnostic?