The Three of Cups occupies the second decan of Cancer in the water suit's zodiacal sequence, ruled by Mercury and carrying the Golden Dawn title Abundance, between the Two under the Moon at Cancer's first decan and the Four under the Moon again at its third. Mercury's presence at a card usually read as unclouded celebration is an odd fit for a planet more often associated with communication and exchange than with festivity, and the Golden Dawn's own materials justify it chiefly by Mercury's rulership of company and social meeting rather than of joy as such.
Pamela Colman Smith's picture, three women dancing in a ring with cups raised amid a harvest of fruit, is widely read as one of her most straightforwardly joyful compositions in the entire deck, and it departs completely from the Marseille pattern, where the Three of Cups is three cups in an unpeopled lattice, its meaning supplied by cartomancers' number-based manuals rather than by any picture of celebration. The harvest setting, echoed nowhere else quite so directly among the Cups pips, ties the card to the reaping season and by extension to a joy understood as the fruit of accumulated effort rather than as a windfall.
The Thoth deck keeps Abundance as its title and, per Harris's method, renders the three cups as a geometric design built around Mercury's glyph and Cancer's, without the dancing figures; Crowley's commentary reads the card as closer to sensual excess than to community as such, a somewhat different emphasis from Smith's picture of shared, sociable joy.