The Great Hymn to the Aten is inscribed in the tomb of the courtier Ay at Amarna, the longest and most complete of several Aten hymns, and it is one of the finest religious poems to survive from the ancient world. It describes the world at night, when the lion comes out and every serpent bites and the land lies in silence, and then the dawn, when the two lands are in festival and people wake and wash and raise their arms. It takes in the chick that speaks inside the egg, the child in the womb, the fish in the river, and the foreign countries of Syria and Nubia, whose peoples the god made with different tongues and different skins. Tradition ascribes it to Akhenaten himself; the ascription is not secure.
Whether Atenism should be called monotheism has been argued for a century and a half and remains open. In its favour: the other gods were not merely subordinated but suppressed, and the hymn says flatly that there is no other. Against it: the king and, in some formulations, his queen remain divine and remain the necessary intermediaries, so what the ordinary Egyptian gained was not direct access to one god but a shorter pantheon with the royal family in it; and the reform touched the state cult far more than it touched what people did in their houses at Amarna, where the excavated evidence shows household gods like Bes and Taweret still in use throughout. Erik Hornung and others have preferred to describe it as a revolution in the state cult that reached monotheistic form without producing a monotheistic society.
The parallels between the Great Hymn and Psalm 104 are close in places (the night with its predators, the dawn and human work, the creator who gives every creature its food), and they have been noticed since the tomb was published. What they mean is disputed. Direct dependence, mediated transmission through Levantine hymnic convention, and independent use of a common Near Eastern repertoire have all been argued, and the gap of some six centuries is a real difficulty for the simplest version of the claim. Sigmund Freud's further step, in Moses and Monotheism, that Israelite monotheism derives from Akhenaten, is not accepted by Egyptologists or biblical scholars and is best treated as part of the history of the idea rather than as evidence for it.