In a single statement, the effect of the sacraments is to infuse justifying grace into men. That which Christ effects is achieved through the sacraments. Christ's humanity was the instrument for the operation of his divinity; the sacraments are the instruments through which this operation of Christ's humanity passes over to men. Christ's humanity served his divinity as "instrumentum conjunctum", like the hand; the sacraments are "instrumenta separata", like a staff; the former can use the latter, as the hand can use a staff. (For a more detailed exposition, cf. Seeberg, "ut sup.", ii. 112 sqq.)