classic waka stream

この世にし楽しくあらば来む世には
虫に鳥にも我れはなりなむ
Roma-ji

Kono yo ni shi tanoshiku araba komu yo ni wa mushi ni tori ni mo ware wa narinamu

English Translation
If in this world here
I can only live in joy,
then in the next world
as an insect or a bird
I will gladly be reborn.
Meaning
If I can enjoy myself in this life, then in the next I will gladly become an insect or a bird.
Commentary
Book Three Miscellaneous Poems 348

Headnote continued from the preceding poem: "Thirteen poems in praise of sake by the Governor-General of Dazaifu, Lord Ōtomo"
This is the eleventh of the thirteen poems in praise of sake by the Governor-General Lord Ōtomo. Buddhism held that breaking the precept against drinking led to rebirth as a beast, but Tabito turns this around: if he can enjoy this life, he does not mind becoming an insect or a bird in the next. His bold affirmation of present pleasures reveals his view of life.
The thirteen poems in praise of sake form a sequence in which Tabito, at Dazaifu, extols wine as a way of rejecting worldly cleverness and consoling life's sorrows, drawing on Chinese precedents such as the Seven Sages of the Bamboo Grove.
The poet, Ōtomo no Tabito, was a son of Ōtomo no Yasumaro. He served as Middle Counselor and Governor-General of Dazaifu before rising to Great Counselor, and died in Tenpyō 3 (731). Steeped in Chinese letters, he was at the center of a poetic circle with Yamanoue no Okura and others while serving in Tsukushi.

First line "If in this world here": shi is emphatic.
Second line "I can only live in joy": araba is a condition.
Third line "then in the next world" pairs with "this world" in the first line.
Fourth line "as an insect or a bird" means whether insect or bird.
Fifth line "I will gladly be reborn": na is perfective and mu expresses resolve, a defiant close.
Author
Ōtomo no Tabito
Source
Manyoshu
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