Ashitazu no yowai shi araba kimi ga yo no chitose no kazu mo kazoetoritemu - Murasaki Shikibu Nikki(English Translation & Meaning)

あしたづの齢しあらば君が代の
千歳の数もかぞへとりてむ

Roma-ji: Ashitazu no yowai shi araba kimi ga yo no chitose no kazu mo kazoetoritemu
English Translation: If I had the years
of the crane that lives so long,
then of your great reign
I would surely count and gather
all thousand years one by one
Meaning: If only I had the long life of the crane, I would surely count, one by one, the thousand years of our young prince's reign.
Commentary: 22 The Fiftieth-Day Celebration

On the first day of the eleventh month of Kankō 5 (1008), the ceremony marking the fiftieth day since Prince Atsuhira's birth was held at the Tsuchimikado mansion. The ladies, dressed in their finest, gathered before the Empress, and Michinaga offered the infant prince the celebratory rice cake. As the banquet wore on, the nobles grew drunk and unruly: the Minister of the Right tore at the seams of a curtain screen, and the Intendant of the Left Gate Guards peered toward the ladies, asking, "Pardon me, but is young Murasaki about here?" Sensing the evening would turn frightfully drunken, Murasaki agreed with Lady Saishō to slip away as soon as the ceremony ended, and they hid behind the dais curtains. But Michinaga had the screens pulled away, caught them both and sat them down, saying, "Compose a poem for me, and I will let you go."
Lady Saishō was the daughter of Fujiwara no Michitsuna and served Empress Shōshi as a lady of high rank. The Intendant of the Left Gate Guards was Fujiwara no Kintō; his calling out for "young Murasaki" is considered the oldest record showing that The Tale of Genji was being read at court, and the first of the eleventh month was later designated Classics Day in Japan.
When Murasaki recited "Ika ni ikaga kazoeyarubeki yachitose no amari hisashiki kimi ga miyo oba," Michinaga murmured "Ah, well composed!" twice and replied with this poem without a pause.
Afterward Michinaga boasted of his own verse to the Empress and joked that he was no poor father to her and she no poor daughter to him. Murasaki felt that his heart, set on his grandson's future even in such drunkenness, was only natural, and thought that it was by being celebrated so warmly that the young prince's glory would grow still greater, musing on a future that a thousand ages could not exhaust.

The opening lines pose a condition, if I had the lifespan of the crane, using the poetic word for crane and an intensifying particle. The crane was said to live a thousand years and was a symbol of longevity.
The lower verses vow that he would surely count out all thousand years, combining an auxiliary of emphasis with one of will. Taking up Murasaki's "how to count" as "I would count and gather," he answers her claim that the years are beyond counting by declaring that he could count them. He also echoes her "your reign," setting a thousand years against her eight thousand, and lets his grandfatherly wish to see the young prince's long life shine through.
Author: Fujiwara no Michinaga
Source: Murasaki Shikibu Nikki
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