There is no greater presence of Our Lord Jesus Christ than the Holy Eucharist. This is because in the mystery of the Eucharist Jesus is not present in another, but rather is the Other. He is not merely present in the Eucharist, but indeed the Eucharist is Him. To look upon and receive the Eucharist is not to look upon and receive a representation of Jesus Christ, but to look upon and receive Him. There is nothing greater in all creation than this mystery.
After the Eucharist, Christ is must fully present in His priests. While the Logos is in all by virtue of all being made in the image and likeness of God, and while He more intimately dwells in Christians by virtue of the reception of His Spirit, divinity, and life in Baptism, He most intimately dwells in His priests through the sacrament of Holy Orders. The priest is not simply a representative of Jesus Christ. When he offers the Holy Sacrifice of the Mass, he does not do so merely as an ambassador or emissary. No, the priest acts in persona Christi. Christ is present in the priest in such a way that it is He who offers Himself at the altar.
In matrimony, Jesus is uniquely present in the husband and wife, who become an icon of the marriage of Jesus to the Church. This marriage is cosmic, bringing together God and man, as well as the Uncreated and created. It is a marriage that entails the whole of creation. Christ’s sacramental presence in the married couple is such that they become a visible image of the mystical union, the wedding feast of the Lamb, a love of mutual submission, sacrifice, and glory.