Nihil obstat

Nihil obstat (Latin for "nothing hinders" or "nothing stands in the way") is a declaration of no objection to an initiative or an appointment.

Apart from this general sense, the phrase is used more particularly to mean an "attestation by a church censor that a book contains nothing damaging to faith or morals". The Censor Librorum delegated by a bishop of the Catholic Church reviews the text in question, but the nihil obstat is not a certification that those granting it agree with the contents, opinions or statements expressed in the work; instead, it merely confirms "that it contains nothing contrary to faith or morals."

The nihil obstat is the first step in having a book published under Church auspices. If the author is a member of a religious institute and if the book is on questions of religion or morals, the book must also obtain the imprimi potest ("it can be printed") of the major superior. The final approval is given through the imprimatur ("let it be printed") of the author's bishop or of the bishop of the place of publication.

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