Ex opere operato

Ex opere operato is a Latin phrase meaning "from the work worked" referring to sacraments deriving their power from Christ's work (ex opere operato Christi) rather than the role of humans. The phrase is commonly misunderstood to mean that sacraments work automatically and independently of the faith of the recipient. However, In order to receive sacraments fruitfully, it is believed necessary for the recipient to have faith. In modern usage, the phrase often refers to the idea that sacraments are efficacious in and of themselves rather than depending on the attitude either of the minister or the recipient. For example, Confirmation might be held to bestow the Holy Spirit regardless of the attitude of both the bishop and the person being confirmed.

In antiquity, the idea led to a schism among the Donatist Christians. The Donatists held that "one of the three bishops who had consecrated Caecilian was a traditor", and therefore Caecilian's consecration was invalid. Furthermore, they held "that the validity of such an act depended on the worthiness of the bishop performing it" and Caecilian and his followers "responded that the validity of the sacraments and of other such acts cannot be made to depend on the worthiness of the one administering them, for in that case all Christians would be in constant doubt regarding the validity of their own baptism or of the communion of which they had partaken."

According to the teaching of the Catholic Church, to receive the fruits of the sacraments requires that a person be properly disposed. This means the efficacy of grace via the sacraments is not automatic. There must be, at least in the case of an adult, an openness to use the sufficient grace which is available in a sacrament. When the recipient is properly disposed, "the sacraments are instrumental causes of grace."

This principle holds that the efficacy of the sacrament is a result, not of the holiness of a priest or minister, but rather of Christ Himself who is the Author (directly or indirectly) of each sacrament. The priest or minister acts in persona Christi (in the person of Christ), even if in a state of mortal sin. Although such a sacrament would be valid, and the grace efficacious, it is nonetheless sinful for any priest to celebrate a sacrament while himself in a state of mortal sin.

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Wikipedia