opus incertum

A kind of masonry formed of small stones of irregular shape touching only at certain points, the interstices being filled with well-composed mortar. IMG:content-0331.png:[blocks in formation] Roman Theol.: Usually employed adverbially ( ex opere opera to ). The expre ion opus operatum (=the work done) was used by medieval theologians to signify that grace was conferred by the sacrament itself, and adopted by the Council of Trent, which, in the eighth canon ( De Sacrament is in genere) of the seventh se ion, anathematizes any one who shall say that the sacraments do not confer grace ex opere opera to . The nece ary dispositions on the part of the recipient are cond it i ones sine qua non; and, according to the Roman view, the grace conferred is due, not to these nece ary dispositions, but to the sacrament as received with these nece ary dispositions. "When we say the sacrament confers grace ex opere opera to, our meaning is that grace is conferred by virtue of the sacramental act itself instituted by God for this end, not by the merit of the minister or the recipient." Bell arm in : De Sacrament is, lib. ii. 1.