Article one sets out the seven Amesha Spentas as the highest tier of Zoroastrian divine beings, each a moral quality and a guardian of a domain of creation. Below that fixed and named tier sits a much larger and less tidy class, the yazatas, "worthy of worship," which article one does not cover and which shows the tradition's devotional life extending well past the seven.
The yazatas number in the dozens across the Avesta and include figures with substantial cults of their own: Mithra, guardian of covenants, invoked wherever a promise is sworn; Anahita, goddess of the waters and fertility; Sraosha, the personification of obedience, who guards the soul on its first nights after death; and Atar, the sacred fire itself, venerated as a yazata rather than merely as a symbol. Several, Mithra especially, carried independent devotional weight strong enough to travel outside Zoroastrianism entirely, most famously into the Roman Mithraic mysteries, where the same divine name became the centre of an unrelated cult with different myths in a different empire.
The distinction between the seven Amesha Spentas and the broader yazatas is also one of kind, not only number. The Amesha Spentas are treated as extensions of Ahura Mazda's own being, which is why article one can describe them as cosmic powers, ethical qualities and guardians of creation at once; the yazatas are worshipful in their own right without that built-in identification, closer in function to the saints and lesser divine figures organising the devotional middle ground of other traditions in this collection.