Major Arcana · Key 13
Death
Read to know yourself, not to surrender yourself: relate to the card; never obey it. These are what two traditions wrote, not predictions.
In Waite's words: The Pictorial Key to the Tarot (1911)
The veil or mask of life is perpetuated in change, transformation and passage from lower to higher, and this is more fitly represented in the rectified Tarot by one of the apocalyptic visions than by the crude notion of the reaping skeleton. Behind it lies the whole world of ascent in the spirit. The mysterious horseman moves slowly, bearing a black banner emblazoned with the Mystic Rose, which signifies life. Between two pillars on the verge of the horizon there shines the sun of immortality. The horseman carries no visible weapon, but king and child and maiden fall before him, while a prelate with clasped hands awaits his end.
There should be no need to point out that the suggestion of death which I have made in connection with the previous card is, of course, to be understood mystically, but this is not the case in the present instance. The natural transit of man to the next stage of his being either is or may be one form of his progress, but the exotic and almost unknown entrance, while still in this life, into the state of mystical death is a change in the form of consciousness and the passage into a state to which ordinary death is neither the path nor gate. The existing occult explanations of the 13th card are, on the whole, better than usual, rebirth, creation, destination, renewal, and the rest.
The upright and reversed meanings above are from Waite's own list of the trumps' divinatory meanings, Part III §3 of the same book; see them all, with his Celtic Cross, on Tarot spreads.
A. E. Waite, The Pictorial Key to the Tarot (London: William Rider & Son, 1911), public domain.
In the Golden Dawn's Book T (1912)
The Child of the Great Transformers; Lord of the Gate of Death
Time, age, transformation, change involuntary (as opposed to 18, Pisces). Or death, destruction (only latter with special cards). [Specially, a sudden and quite unexpected change.]
Correspondences
Hebrew letter: נ (Nun, 'fish') — path 24 on the Tree of Life.
On the Tree: path 24 joins Tiphareth and Netzach · see it on the map
Attribution: Scorpio.
(Classical Golden Dawn / Book T attribution. Modern decks add an outer planet — Uranus, Neptune, or Pluto — to the three elemental trumps.)
Astrological attribution (Book T)
Book T as printed in The Equinox I(8), 1912, public domain (notes in square brackets are Crowley's). The correspondences are this site's compilation from Book T. Open it in the Golden Dawn deck.