After I completed an evening's talk and prayer session, a young man wanted to discuss his role in the Church. He was, he said, encouraged by what I said, and was eager to play a more active role in spreading the Gospel. I told him that his desire was exactly what Vatican II had in mind when it affirmed the role of the laity as participation in the saving mission of the Church. I said Vatican II insisted that all Catholics are commissioned to the apostolate by Jesus himself (cf. Lumen Gentium, #33), and that was certainly the spirit of the Council.
He winced a bit and expressed concern over Catholics who talk about the "spirit of the Council" rather than the letter of its documents. He wanted to be cautious about laymen who in his assessment overstep their bounds and justify their thinking and actions by appealing to some vague spirit of Vatican II. He then quoted a Catholic priest who said on TV, "If you ever find the spirit of the Council, kill it!"
I was shocked by that advice. I replied, "Ah, but Paul says, 'The letter brings death, the spirit gives life'" (cf. 2 Corinthians 3:6). I did admit to him that there are people who carry the Council and its spirit to an extreme, but at the same time I cannot imagine that the extraordinary gathering of Bishops we call Vatican II had no lingering spirit to guide us.
Pope Benedict XVI has on occasion warned against interpreting the changes of the Council as advocating a complete rupture with the past, as discontinuity. The pope prefers to think of Vatican II as proposing reform not repudiation. He has righly expressed consern that some people ignore the letter of the documents and focus solely on what they perceive to be the "spirit of the Council."
The Church, of course, cannot simply reject the foundational dogmas of its magisterium, but it does (and sometimes must) reverse some teachings and practices advocated in the past.
For example, Pope Pius IX, in his Syllabus of Errors, said it was wrong to hold that "every man is free to embrace and profess that religion which, led by the light of reason, he may have thought true." A hundred years later the Second Vatican Council in its Declaration on Religious Liberty declared that the human person has a right to religious freedom (#2). That is a change.
Vatican II, in effect, reversed the teaching of Pope Pius IX. In no place did it change defined dogma. Pope Benedict's concern about a radical discontinuity is more than valid when we consider defined dogma. If anyone uses the notion of "the spirit of Vatican II" to overturn defined dogma, he misunderstands theology and Vatican II.
It is my conviction that we need to re-read the Council documents, to find out what they really say, and move forward in the spirit those documents convey. I have to admit that the documents often reveal the compromises in theology and wording that opposing groups of Council fathers (the bishops) demanded in order to pass the various constitutions and decrees. Nevertheless, the give-and-take wording of the documents and the instances of ambiguity do not invalidate the sense of direction the Council intended to take.
There can be no doubt that the Council emphasized the role of the laity and urged their participation "in the saving work of the Church" (cf. LG, #33). Careful to maintain the distinction between laity and hierarchy, insistent on the divine role of the ordained, the Council nonetheless confirmed the cooperation that laity and pastors must foster in order for the Church to fulfill its mission in the world (cf. LG, ##37-38).
I know there is a difference between spirit and Spirit, but since I believe the Holy Spirit was present at the Council, I also believe that there is a lingering sense of direction (a spirit) from that Holy Spirit which helps us to interpret the letter of the documents and encourages our fulfilling the mission as well. I very much oppose killing the spirit of Vatican II. If you find it, listen to it, test it against the Council's teaching, and then, if it is valid, let it be your inspiration and guide!