Imagine a man dissatisfied with his marriage who decides to have an affair. He doesn’t go to church anymore, and hasn’t prayed in years. He’s with his girlfriend, and doesn’t want to use a condom, but he feels guilt about the possibility of bringing home disease to his wife. But then he rationalizes “the church says condoms are immoral, so I won’t use one. No point in compounding evil.”
It’s not that farfetched. There are cultures in parts of the world where cheating is rampant and the people are (at least nominally) catholic and use the church’s ban on condoms as an excuse not to be safe, and are bringing home AIDS to their spouses.
I personally think that condoms are evil when they’re used within a marriage. I think if the sex act is already illicit, then condoms don’t make it any more wrong, and in fact might lessen the wrongness.
(Note, this is hypothetical, it’s not about a decision I’m facing in my own life

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