A mixture of oil of olives and balsam, blessed by a bishop in a special manner and used in the administration of certain sacraments and in the performance of certain ecclesiastical functions. That chrism may serve as valid matter for the Sacrament of Confirmation it must consist of pure oil of olives, and it must be blessed by a bishop, or at least by a priest delegated by the Holy See. These two conditions are certainly necessary for validity; moreover it is probable that there should be an admixture of balsam, and that the blessing of the chrism should be special, in the sense that it ought to be different from that which is given to the oil of the sick or the oil of catechumens. (Cf. Lehmkuhl, Cas. Cons. II, n.102.) If either of the last two conditions is wanting the sacrament will be doubtfully valid. To deal with the subject in a sufficiently exhaustive manner, it will be enough to touch upon (1) the origin and antiquity of chrism; (2) its constituent nature; (3) its blessing; and (4) its use and symbolical significance.
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