The bishops did an excellent job of applying Aquinas’ understanding of conscience to contemporary society, said University of Alberta professor of philosophy and Aquinas scholar Matthew Kostelecky.

“The bishops are correct that we need to think about the role we would assign to conscience and the extent to which standards of professional conduct can override somebody’s personal conscience,” he said.

The concrete examples the bishops cite relate mostly to hot-button topics of abortion, contraception and same-sex marriage, but the role of conscience can’t easily be confined to any one set of issues, said Kostelecky.

“Whether I’m a professor or a public servant or a business person, the role conscience plays is a fundamental role in terms of how I see myself carrying out that larger role of the common good,” he said.

Basilian Fr. Bob Holmes believes every Christian is called to be a conscientious objector at some point in their lives — whether the issue is war or abortion or the environment or refugees.

“They (the bishops) are somehow stuck on sexual ethics right now, but the same principals apply to all of the moral decisions we make. And killing people is one of them,” said the chaplain to Christian Peacemaker Teams in Toronto. “People have a right to say I won’t do that, under any circumstances.”

Exercising freedom of conscience is not a simple matter of following your gut, yielding to emotion or indulging political prejudice, Holmes said.

“I agree with the bishops that we have to form our consciences. We have to really try to learn what is right and true in a given situation then act on your own conscience,” he said.

It doesn’t surprise Catholic Civil Rights League of Canada executive director Joanne McGarry that the bishops have focussed on sex and abortion. “We have a problem in Canada, especially in the areas of medicine,” she said.

The CCL has repeatedly been involved in court and human rights tribunal proceedings that pit the rights of sexual minorities against the right to free expression of religion.

“There’s a great deal that by it’s very nature is going to have to be worked out case by case with practical accommodation,” McGarry said.

Few realize how much we owe Aquinas when we invoke the idea of conscience.

“In some ways, our grasp of conscience in the modern world is very poor, in fact,” said Aquinas scholar and professor of systematic theology at Regis College, Fr. Gilles Mongeau.

“Very impoverished compared to the kind of rich reflection done by Aquinas.”

Aquinas was the common ground the fathers of Vatican II stood on when they spoke of conscience in the “Pastoral Constitution on the Church in the Modern World” (Gaudium et Spes) and the “Declaration on Religious Liberty” (Dignitatis Humanae). When the Vatican II bishops wrote about the essential freedom that must be guaranteed to “Christians acting individually or collectively in their own name as citizens guided by the dictates of a Christian conscience,” (Gaudium et Spes, 76) they were applying Aquinas to the 20th century.

“It will be a long time before we can surpass what Vatican II had to say about conscience,” notes Mongeau.

It is a very modern concern. Canadian philosopher John Raulston Saul in The Unconscious Civilization criticizes modern capitalist societies for reducing the role of conscience to a species of consumer choices, even when voting.

For Saul the exercise of conscience is necessarily political and presumes that society must have a moral and political purpose.

For the Catechism of the Catholic Church conscience isn’t only “man’s most secret core and his sanctuary” but a “voice, ever calling him to love.” (CCC 1776)

The Christian idea of what it means to be human is necessarily social — which is why the bishops speak of conscience in terms of love and the common good, said Kostelecky. “The common good is typically the Catholic response to the modern split between the private and the public,” he said. “My responsibility doesn’t start and end with myself. And it’s not merely setting up a barrier of negative rights so that other people are ensured I don’t encroach upon them. But I need to go beyond and make sure that the common good is served.”

Our sense of right and wrong must apply to everything from economics to education, he said.

“Ethical considerations are to be reflected upon and debated precisely because that’s what makes us human,” said Kostelecky. “We can’t extricate ourselves from the community. If we just look at ourselves as consumers, then we’ve made a mistake.”

Religious people aren’t making a selfish demand when they demand freedom of conscience and freedom of religion, said Mongeau. Conscience impels Christians to be of service to everyone.

“That’s all that believers want — the opportunity to make a contribution to public conversation on the common good,” said the Jesuit scholar. “Very often the social expectation is that religion will be a problem rather than part of a solution.”

When the bishops look to Aquinas for guidance on how conscience and religion fit into contemporary debates about clubs for gay students in Catholic schools or civil marriage commissioners refusing to marry gay couples, they’re not proposing a narrow religious perspective. “The Christian tradition on conscience is formed by the Gospel — transformed and shaped by it,” said Mongeau. “But it’s been in dialogue with the best of the philosophical and intellectual tradition — which includes its political dimension.”

In Aquinas’ world you’re not really free unless you seriously apply your conscience to what you think, what you say and what you do.

“For somebody to make a decision in conscience — when we want to use that language — they have to be functioning at a pretty mature level, both psychologically and spiritually,” said Mongeau. “They have to be moving from a place of personal freedom that’s pretty demanding, in fact.”