Liszt described the prelude as “a sort of magic formula which, like a mysterious initiation, prepares our souls for the sight of unaccustomed things, and of a higher signification than that of our terrestrial life.”

Wagner’s own explanation has been translated into English as follows:

“Love seemed to have vanished from a world of hatred and quarreling; as a lawgiver she was no longer to be found among the communities of men. Emancipating itself from barren care for gain and possession, the sole arbiter of all worldly intercourse, the human heart’s unquenchable love-longing again at length craved to appease a want, which, the more warmly and intensely it made itself felt under the pressure of reality, was the less easy to satisfy, on account of this very reality. It was beyond the confines of the actual world that man’s ecstatic imaginative power fixed the source as well as the outflow of this incomprehensible impulse of love, and from the desire of a comforting sensuous conception of this supersensuous idea invested it with a wonderful form, which, under the name of the ‘Holy Grail,’ though conceived as actually existing, yet unapproachably far off, was believed in, longed for, and sought for. The Holy Grail was the costly vessel out of which, at the Last Supper, our Saviour drank with His disciples, and in which His blood was received when out of love for His brethren He suffered upon a cross, and which till this day has been preserved with lively zeal as the source of undying love; albeit, at one time this cup of salvation was taken away from unworthy mankind, but at length was brought back again from the heights of heaven by a band of angels, and delivered into the keeping of fervently loving, solitary men, who, wondrously strengthened and blessed by its presence, and purified in heart, were consecrated as the earthly champions of eternal love.

“This miraculous delivery of the Holy Grail, escorted by an angelic host, and the handing of it over into the custody of highly favored men, was selected by the author of Lohengrin, a knight of the Grail, for the introduction of his drama, as the subject to be musically portrayed; just as here, for the sake of explanation, he may be allowed to bring it forward as an object for the mental receptive power of his hearers.

“The prelude is scored for three flutes, two oboes, English horn, two clarinets, bass clarinet, four horns, three trumpets, three trombones, bass tuba, kettledrums, cymbals, and strings.”