I don’t believe it is. It may be legally. But I don’t think you have a moral obligation to rent to a gay couple. There are plenty of other people who have no issue renting to them. It’s not like they’ll be out on the street.
If you have a selection of 3 tenants I think it’s a perfectly morally legit to rule one out because they are a gay couple and you don’t want to facilitate their lifestyle.
By that logic you wouldn’t rent out to anyone who isn’t Catholic then, since they’re not living a moral lifestyle. Unless that criteria only applies to gay people, but that’s definitely discriminatory.
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