Arakajime kimi kimasamu to shiramaseba kado ni yado ni mo tama shikamashi o

あらかじめ君来まさむと知らませば
門に宿にも玉敷かましを

Roma-ji: Arakajime kimi kimasamu to shiramaseba kado ni yado ni mo tama shikamashi o
English Translation: Had I known beforehand
that you, my lord, would come here,
had I only known,
at my gate and in my house
I would have spread out jewels
Meaning: Had I known beforehand that you would come, I would have spread jewels at my gate and throughout my house.
Commentary: Book Six Miscellaneous Poems 1013

Headnote: "Two poems from a banquet when the junior minister Tachibana and other gentlemen gathered at the house of Prince Kadobe, President of the Board of Censors, in the first month of spring in the ninth year of Tenpyō, the year hinoto-ushi"
This is the host's poem of welcome: had he known in advance that his guests were coming, he would have laid jewels at his gate and in his house to receive them. By describing, as a mere supposition, a hospitality he was unable to offer, he conveys all the more his heartfelt joy at the visit.
According to the headnote, these two poems come from a banquet held in the first month of Tenpyō 9 (737), when officials led by the junior minister Tachibana gathered at the house of Prince Kadobe, President of the Board of Censors. The junior minister Tachibana is thought to be Tachibana no Sai. The host, Prince Kadobe, composes a poem welcoming his guests, and Tachibana no Fuminari answers on the guests' side, forming an exchange of banquet greetings.
The left note reads "The above poem is by the host, Prince Kadobe," which identifies him as its author. The note also adds that he was later granted the surname Ōhara no Mahito.
The poet, Prince Kadobe, was a member of the imperial family in the Nara period who served as governor of Ise, President of the Board of Censors, and Master of the Right Capital. In Tenpyō 11 (739) he was granted the surname Ōhara no Mahito together with Prince Takayasu and left the imperial family.

The phrase "I would have spread out jewels" is taken up directly in the first line of 1015, "Rather than spreading jewels," the poem later added by Prince Enoi, so that the two poems form a pair between an imagined welcome and the joy actually felt.
The first line, "Had I known beforehand," means "in advance," and shows that the guests' visit was unexpected.
The second line, "that you, my lord, would come here," uses "kimasu," an honorific form of "to come," expressing respect toward the guest.
In the third line, "had I only known," "-mase" is a form of the counterfactual auxiliary "mashi," which answers "-mashi o" at the end of the poem and sets up a supposition contrary to fact: had I known, when in truth I did not.
The fourth line, "at my gate and in my house," shows the host readying his welcome from the front gate to the inner rooms.
The final line, "I would have spread out jewels," ends with the counterfactual "-mashi o." While taking the form of regret over what could not be done, it expresses with playful exaggeration the joy of receiving guests. Spreading jewels was a customary image for the finest welcome offered to a noble visitor.
Author: Prince Kadobe
Source: Manyoshu
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