Can I use a medical treatment that resulted from a sinful act?

Hypothetically, if I were to use a vaccine for my child that was derived from the use of fetal stem cells, would it be sinful? I know it came from this research and I would be acting by my will. I am unsure if this is a cause of scandal or direct participation in a sin. Furthermore, if a long time ago (say 30 years), the sinful medical work was done that eventually resulted in a vaccine years later, could I use the vaccine now?


That’s a very good question. Morally, does time make a difference in these situations?

Can we use, for example, the fruits of the research of the nazis on their prisoners i.e. immersion in ice water to study the effects on fliers that were downed in the North Atlantic?

Perhaps if the evil were recognized and ceased?

If it’s an ongoing evil, then methinks not…but then again, if it’s an ongoing evil it’s pretty clear that such is not morally acceptable.

I don’t know if there’s a simple answer to this question.

On Vaccines Made From Cells of Aborted Fetuses

It’s long and rather dense reading. Here’s a quote from the end:

The lawfulness of the use of these vaccines should not be misinterpreted as a declaration of the lawfulness of their production, marketing and use, but is to be understood as being a passive material cooperation and, in its mildest and remotest sense, also active, morally justified as an “extrema ratio” due to the necessity to provide for the good of one’s children and of the people who come in contact with the children – pregnant women.

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