Whys about Vatican II

Attempting to answer  questions posed by a young Catholic about about events in the Church after Vatican Council II has to be somewhat experiential rather than theoretical: I mean we can only offer possible explanations, not firm facts. Accepting the inadequacy of such information these are my responses:

The jump in vocations after the Council reflected an enthusiastic response to the immediately evident changes, particularly in the celebration of the Liturgy in the vernacular and the involvement of many in the new ministries to which the laity were called. The Liturgy particularly opened up the richness of the Scriptures to many unfamiliar with them and the joyful celebration of the Eucharist accompanied by contemporary hymns involved the whole community in the prayer of the Church.  Leadership of such a vibrant community was extremely attractive to an idealistic young Catholic.

The departure of many from the active ministry of the priesthood was influenced by many different motives.

One was the problem of celibacy; in the immediate aftermath of the Council there was discussion about making celibacy optional raising hopes by those who found it difficult and when these hopes were dashed some left. Others found it difficult to adjust to the reduction of the role of the priest to leader of the community rather than autocratic pastor as in the old system, or had difficulty with the new liturgy etc.. Others still had embraced the changes enthusiastically but were disheartened by the slow pace at which reforms were implemented and by what they saw as authoritarian efforts to derail the mandates if the Council.

A further problem was the ambivalence of many teachers who lacked adequate  understanding of the changes which occurred. Actually poor formation in many seminaries both before and after the Council was a contributing factor. Many young enthusiastic priests were ordained who were immature and who had unrealistic concepts of their role in the life of the community.

The difference between priest and laity is the basis of a whole document of the Council but it is essentially tied to the sacrament of ordination. In other words it is a sacramental difference much as the difference between a baptized and an unbaptized believer. The sacrament confers power exercised in the formal acts of the Church  or more accurately of the sacramental Christ  in encountering the individual.  The layman may reflect Christ to others but not in an official capacity. (I'm not satisfied that this is an adequate answer but it is a short one.)

The difference between a layman and a priest with a Master's or Doctorate in Theology or other religious studies is zero in terms of the degree. The difference between priest and layman is that outlined  in the last response. There may be differences in their  mobility; the lay theologian is free to teach anywhere, the priest may need his religious superior's permission to accept a position. The priest is more subject to review and censure for his views which question or diverge from the official line than is the lay theologian.