Christ works in the sacraments
The reception of the grace that is in the sacraments is very effective in our soul because it is Christ who confers the grace. By the mere fact, for example, that we turn on the faucet, water comes out. The water does not come because we subjectively believe that water will come forth. The divine life of Christ is poured into our soul by the mere fact that we receive the sacrament. Of course, we must not put an obstacle in the way of receiving the sacraments. But it is Christ who baptizes; it is Christ who forgives sins. There are ministers, of course, and there are bishops and priests, but we loan Christ our eyes and our hands and our limbs. It is he who gives the grace. That, incidentally, is why, even though you received the sacrament from an unworthy priest, it would still be a sacrament. Sanctification does not depend upon the priest. Because sunlight comes through a dirty window, sunlight is not polluted. A messenger may be very ragged, but he can still bear the message of a king.