That reference to an “informed conscience” brought to mind my own experience at Catholic school. I was in sixth grade when the parish priest visited our religion class to take questions. That kind of classroom visit was a post-Vatican II bonding exercise, I suspect. Kumbaya Catholicism, circa 1973.

But the priest was taking questions, and I had a question. If God is all-merciful, how can there possibly be a hell? I could not imagine a sin so egregious that it was beyond the reach of my own capacity for mercy, and I was only a human being. I was certainly not God.

The priest did not point out that I was a little girl, intellectually ill equipped to question theology. He explained that God had given me a conscience and a good mind. In spiritual matters I must study church teachings and listen to the explanations of my elders and pray for discernment — and if I did all those things and nevertheless came to a conclusion at odds with my church’s position, I was not obliged to follow church teaching. In fact, I was obliged to do the opposite: to honor the moral wisdom of my own conscience over the teaching of my church.

I don’t recall whether this priest referred explicitly to the primacy of an informed conscience, but I have never forgotten his message, a principle of faith that goes back to St. Thomas Aquinas and was recently reaffirmed by Pope Francis. It’s why officials at Brebeuf Jesuit defied the archbishop of Indianapolis. It’s why my husband and I took our children to the Supreme Court steps the morning the Obergefell decision was announced. Love will never truly win until everyone stands up for it.

Catholics today don’t hear much about the primacy of an informed conscience because many priests take the position that a conscience at odds with the church is by definition insufficiently informed. But the primacy of an informed conscience belongs as deeply to church tradition as the current brand of pastoral authoritarianism does. It is time for Catholics to remember it again and stand up for their brothers and sisters in same-sex marriages, as Brebeuf Jesuit has done, even if it means defying the teaching of their own imperfect church.

“No union is more profound than marriage, for it embodies the highest ideals of love, fidelity, devotion, sacrifice and family,” wrote Justice Kennedy in the Obergefell decision. “In forming a marital union, two people become something greater than once they were.” In defending the moral and spiritual equality of those in same-sex marriages, Christian believers too have the opportunity to become something greater than once they were.

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