Ex opere operato is a Latin phrase meaning, literally, "from the work performed" i.e., "by virtue of the action," and is used in Roman Catholic theology to mean that the blessing of a sacrament, e.g., is efficacious independently of the moral merits of the officiating priest or the recipient of the sacrament.
In contrast, ex opere operantis (literally, "from the work of the doer") means that the efficacy of the blessing or sacrament is dependent on the faith stand of the person receiving it.
©ALBERITH
210820lch