This waka is Addendum 13 and the last waka in the Shunjusha text of Dogen Zenji Wakashu (Collection of Dogen Zenji’s Waka). Nio is the old name of the waterfowl called kaitsuburi (grebe, Tachybaptus ruficollis). Lake Biwa, the largest lake in Japan located in Shiga Prefecture, was called Nio no umi (Lake of Nio) because many grebes and other water fowl live there. Today the grebe is the prefectural bird of Shiga Prefecture. Lake Biwa can be seen from Mt. Hiei where Dogen practiced for several years as a novice.
Yabase is the name of a town on the east coast of Lake Biwa in Kusatsu City in Shiga Prefecture. In the ancient times, Yabase was well known as the port of a ferry boat that connected Kusatsu and Otsu, creating a short cut to travel to the capital Kyoto that was much shorter than walking around the lake. Afumi in the last line is a paronomasia that combines oumi, the old name of Shiga Prefecture) and “the person to meet.” Afu can mean to meet (au, 会う), and mi (身) means a body or a person.
The first three lines of this waka describe the scenery of Lake Biwa. A ferry boat is sailing on the lake offshore from Yabase. Then, Dogen (if this waka was written by him) says, even though it is a short cut, he still wishes to push his boat out to meet with the person on the ferry as soon as possible.
This waka was found by Dr. Doshu Okubo in Toyo-wakashu (藤葉和歌集) a collection of waka compiled in the Nanbokucho period (1336 – 1392) by Ogura Sanenori. Dr. Okubo included this waka in Dogen Zenji Wakashu as a part of Dogen Zenji Zenshu published by Chikuma Shobo in 1970. Okubo wrote in his Dogen Zenji Den no Kenkyu (Study of the Biographies of Dogen Zenji, Chikuma Shobo, 1966) that this waka might be evidence that Dogen Zenji attended gatherings of aristocrats for writing waka while he lived in Fukakusa.
In Toyo-wakashu, this waka is included in the section of love poems. People considered this to be a poem by a person who wishes to meet his or her lover as soon as possible so he/she wishes to push out the boat. Because of this, some people hesitated to consider this written by Dogen. Another interpreter thinks this is not necessarily a love poem. Only the compiler of the waka collection thought this waka is about the sentiment of a lover.
I have no basis to decide whether this waka was written by Dogen Zenji or not. The only thing I can suggest is that in Shobogenzo Gyoji (Continuous Practice), Dogen wrote about his encounter with his late master Rujing (Nyojo):
Manoatari senshi wo miru kore hito ni afunari.
I saw my late master with my own eyes; this is [truly] meeting with a person.
If this waka was written by Dogen, I think this expression “hito ni afu (to meet a person)” could mean to meet with a true person of the Way. In Shobogenzo Zuimonki, Dogen talked about his meeting with many such people who completely dedicated their lives to the Buddha Way.
Dogen also wrote in Shobogenzo Uji (Being time):
Ware hito ni au nari; hito ware ni au nari; ware ware ni au nari; shutu shutu ni aunari.
I encounter a person; a person encounters a person; I encounter myself; going forth encounters going forth.
This quote from Uji has something to do with the koan included in Shinji Shobogenzo (Dogen’s collection of 300 koans) case 92:
Zen master Sansheng (Dharma heir of Linji) said, “When I meet a person, I go out. When I go out, I don’t guide the person.”
Cunjiang of Xinghua Monastery said, “When I meet a person, I don’t go out. When I go out, I guide the person.”
Zen master Yuanwu, the commentator of the Blue Cliff Record; Hongzhi, the Soto Zen master who composed verses on the hundred koan included in the Book of Serenity; and Dogen’s teacher Rujing all mentioned this koan in their Dhama Hall discourses.
I think that if this waka was composed by Dogen, meeting “with a person” means meeting with anyone devoted to the Way.