Hier sehe ich eher: 'ecclesiastical bank' . . .

'church bank' klingt doch sehr nach 'Kirchenbank' (mit Knievorrichtung) . . . ;-)

But remember, in English a bench (or in a church, a pew) is not the same word as a bank.

I don't really like either 'ecclesiastical bank' or 'church bank.' It would probably be better to use an adjective like church-sponsored, church-affiliated, church-related, church-owned, etc., but without more context (what country? what century? what church?), who knows.

Liga-Bank, which was founded by Catholic priests, is Germany's oldest church bank.

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