Our Lord, in the Holy Eucharist, gives Himself to us in a manner that none can fathom. The manner in which He gives Himself is so worthy of admiration that, were the Seraphim to reflect on it for all of eternity, they would not be able to exhaust the idea; God gives Himself to man in the species of bread and wine.
He thus penetrates man and is assimilated by him.
We will never be as intimate with someone as we may be with Our Lord in the Holy Eucharist.