Now, Cornwell makes a point about the dictatorial nature of the sacrament of Confession that led to the rejection of Church teaching on Catholic sexual matters after the 1960s, particularly the encyclical letter Humanae Vitae on contraception. I dispute that claim.
Generally accepted in orthodox Christian thought is the principle lex orandi, lex credendi. The law of prayer is the law of belief. Sometimes this is extended to include lex vivendi, the law of life, showing the intimate connection drawn by St. Paul in Romans 12:1-2 between the moral and spiritual/liturgical life. They are so close as to be one and the same for those seeking perfection in charity.
By the 1960s and 1970s, attempting to follow the call of the Council for a renewal in moral theology, moral theologians put out a new moral theology. They were dissatisfied with the Church's articulation of the teaching on conscience. It showed what was good and evil, and there was no decision-making, only discernment of what really is good. For these dissidents, personal moral maturity was reached when one could make decisions, distinct from judgments, about something being good or evil, and God's counsels and the commandments served as general norms that could not possibly cover each and every situation man faces. In fact, God basically is supposed to give a pat on the back when one says, "Thanks God, but yo dude, I got dis," when making a moral decision.
So there might indeed be a scenario when murder or something else contrary to the commandments is justifiable, although at every occasion we must ask, "Is this an occasion where God's law saying this is unrighteous in fact does not apply and this is righteous?"
The problem is that God is the Creator of all. He knows all in His infinite mind, so it stands to reason that He could envision every situation encountered by man, meaning that one can perceive good and evil (what St. Thomas calls synderisis) and can judge in each particular case what is good or evil (what he calls conscience), since God speaks to him, drawing his attention with divine and binding authority to what is written on the heart (what Vatican II refers to also as conscience). So it's dangerous to think otherwise.
In fact God gave us reason, which in the tradition of theology is highly emphasized as our being made in God's image, wherein we can discern God's existence and through grace come to know Him, come to know what is in His mind, and come to be like Him (as we are created in His image and likeness). It would be completely inappropriate to give us the gift of reason, expect us to conform to God's likeness but then give us a law that does not require us to conform to it. It would be wrong for the Lord to have commanded us to love as He loves us if we have no way to measure ourselves. It would be wrong to allow us to help craft our own destinies but then allow us to make everything up, which is in effect what happens in certain moral theologies: people make it up, and it's not actually true, because it's relative, or only true to some extent, and it's subject to human fallibility.
This post might as well be called, "Why I am Devoted to the Older Liturgy." I am a master of very few things, let alone Truth. I struggle to control my body, so how can I come to be like God mostly or totally through my own decision-making? We can participate in God's inner life as He graciously allows and desires. We can participate in our own creation, for God did not create the universe completely and perfectly, and to do so would be completely inappropriate for us as rational creatures. Creation is in a state of journeying until the fullness of Time, but only through the Divine Will guided by the disposition known as Divine Providence. We are meant to move by grace towards perfection, just as our Heavenly Father is perfect. But our own role is directed by the grace of God to Himself, always in a secondary role, one that is tremendously beautiful.
By all of this I mean that the principles that guide our proper understanding through the mind of Holy Mother the Church on the sacred liturgy and its relation to the moral sphere cannot be held with other moral theologies in opposition to Tradition and Scripture. The liturgy was gutted in favor of one that has limited connections to the older missal, and many priests just made even more things up, including the anaphora! (I make this criticism fully aware of the awesomeness of this past week's lections and orations: it's a rare example of something that might be worth keeping...). Hence a large-scale rebellion occurred, rejecting Pope Paul VI, of blessed memory, and his affirmation of the dignity of human life and the dignity of the marital act in relation to expressing the human life and bringing forth new life.
Pope Benedict XVI, whose episcopal motto is "Co-Worker with the Truth" highlighted in a homily how this life of living the Commandments properly is all about loving as God loves us, loving so that we might be perfect in Heaven. In effect, the Commandments become redundant:
It is first and foremost a “yes” to God, to a God who loves us and leads us, who carries us and yet allows us our freedom: indeed, it is he who makes our freedom real (the first three commandments). It is a “yes” to the family (fourth commandment), a “yes” to life (fifth commandment), a “yes” to responsible love (sixth commandment), a “yes” to solidarity, to social responsibility and to justice (seventh commandment), a “yes” to truth (eighth commandment) and a “yes” to respect for other people and for what is theirs (ninth and tenth commandments). By the strength of our friendship with the living God we live this manifold “yes” and at the same time we carry it as a signpost into our worldBy the way, this is from the Nativity of the Blessed Virgin Mary, whose great "Yes" we should follow. Ecce ancilla Dominae: Fiat mihi secundum verbum tuum.