21Carey, John. "Time, Memory, and the Boyne Necropolis." Proceedings of the Harvard Celtic Colloquium 10 (1990): 24-36.
Carrey suggests that the meaning and usage of Newgrange was passed down through legend and practice for 5,000 years. "On the literary side, the earliest of the tales may go back to eighth-century originals, but the high degree of variation between them suggests that the legend continued to have an oral basis throughout the medieval period. Even if we posit extremely early written sources for all of the versions, however, we are still left with an oral tradition spanning approximately four thousand years. Besides the sheer duration of this interval, we must reckon with the momentous cultural developments which it included: the conversion of the Irish to Christianity and also, almost certainly, the arrival of Celtic language in Ireland. Could an idea survive such far-reaching changes, and so many centuries? No a priori dogma can settle such a question in advance: the evidence must be considered on its merits. In my own opinion the specific localization of the legends, taken together with the apparent uniqueness of the design of Newgrange, cannot reasonably be dismissed as mere coincidence."
Aengus' semantic trickery involving time that gained him the possession of Newgrange from his father is analogous to his father's manipulation of time that contracted Aengus' gestation and birth into a single day. This emphasis on the passage of time in the legendary tales of the monument is given a astronomical resonance in the yearly appearance of the sun through the roof-box on the morning of the Winter Solstice. As authors Brendan Purcell and Dorothy Cross put it, "Far more than words, our deeds reveal and communicate who we are. In a gigantic drama between stone and sun, re-enacted every year, the neolithic people who built Newgrange expressed their grasp of the mysterious answer to their quest for the meaning and order of their existence. They deployed all their technological, architectural, artistic, astronomic and mathematical skills to elevate midwinter sunrise into a cosmic YES at the zero point of cosmic forsakeness." (Purchell, Brendan, and Dorothy Cross. "Newgrange: Between Sun and Stone." The Crane Bag: The Other Ireland 2.1/2 (1978): 89-95.)

Within her poem "Carnival," Nuala Ní Dhomhnaill deals with a this theme, but on an more personal, and mortal, level.

If we were gods
here at Newgrange—
you Sualtam or the Daghda,
myself the famous river—

we could freeze the sun
and the moon
for a year and a day
to perpetuate the pleasure
we have together.

Alas, it's far from gods
we are, but bare, forked creatures.
The heavenly bodies stop
only for a single, transitory moment.

(Ní Dhomhnaill, Nuala, and Paul Muldoon, trans. The Astrakhan Cloak. Winston-Salem, NC: Wake Forest UP, 1993. 13.)