鵲巣をや Kasasagi su wo ya
つくるらん Tsukuru ran
眉にかかれり Mayu ni kakareri
蜘蛛のいと Sasagani no ito
On his head,
a magpie might make its nest,
a spider's web is
hanging from his eyebrows.
"Itadaki" means "crown of head" or "summit of mountain." Here it refers to the crown of the head of a person who is sitting in zazen. "Kasasagi" is a black bird similar with a crow. Its English name is magpie. In Europe, a magpie generally has a negative association, and has been demonized some countries. However, in China and Korea, magpies are considered a bird of good fortune. In Japan, it is said that magpies were imported from Korea in the 16th century. Since then magpies live in various places in western parts of Japan. Probably Dogen did not have a chance to see this bird with his own eyes except while he stayed in China, but he used the name of this bird which appears in Buddhist texts. "Ran" is an auxiliary verb to show conjecture. Also, in this waka Dogen actually did not see the bird making a nest. "Sasagani" literally means a little crab, but here it refers to a spider. A spider is called a little crab, probably because it has many legs and walks like a crab. "Ito" is a thread or web."Kakareri" is a statement, not conjecture. Dogen actually sees the spider's web hanging from the eyebrow of the person sitting.
In the Denkoroku (the Record of Transmitting the Light), Keizan Jokin wrote about Shakyamuni Buddha's practice after he left his father's palace as follows:
"Shakyamuni Buddha was of the Sun Race in India. At the age of nineteen he leaped over the palace walls in the dead of night, and at Mount Dantaloka, he cut off his hair. Subsequently, he practiced austerities for six years. Later, he sat on the Adamantine Seat, where spiders spun webs in his eyebrows and magpies built a nest on top of his head. Reeds grew up between his legs as he sat tranquilly and erect without movement for six years. At the age of thirty, on the eighth day of the twelfth month, as the morning star appeared, he was suddenly enlightened."
In the Hokyoki, Dogen recorded his master Rujing's saying about zazen and dropping off body and mind:
"The zazen of arhats and pratyekabuddhas is free of attachment yet it lacks great compassion. Their zazen is therefore different from the zazen of the buddhas and ancestors; the zazen of buddhas and ancestors places primary importance on great compassion and the vow to save all living beings. ... In buddhas' and ancestors' zazen, they wish to gather all Buddha Dharma from the time they first arouse bodhi-mind. Buddhas and ancestors do not forget or abandon living beings in their zazen; they offer a heart of compassion even to an insect. Buddhas and ancestors vow to save all living beings and dedicate all the merit of their practice to all living beings."
The source of both Keizan's description of Shakyamuni's practice at Mount Dantaloka and Rujing's statement about compassion in buddhas' and ancestors' zazen seems to be Nagarjuna's Daichidoron, his commentary on the MahaPrajna Paramita Sutra. In this text, right after Rujing says that buddhas and ancestors do not forget compassion toward all living being including insects, Nagarjuna refers to a story about a mountain sage who was Shakyamuni in one of his past lives. Shakyamuni was then called Rakei Sennin, the mountain sage whose hair looked like a conch-shell. While he was sitting immovably in upright posture like a tree, a magpie made a nest on his head and laid eggs. The sage thought that if he stopped sitting and moved, the mother bird would be frightened and not return, then the baby birds would die. Therefore he continued to sit without moving until the mother and the baby birds flew away. I cannot find any source about the spider's web in the older texts.
This story tells that the bodhisattva practiced with all living beings including birds and insects and tried not to frighten or harm them. Even while he was sitting, he considered living beings as part of his life.
A modern commentator, Rev. Nanboku Oba, in his commentary on this waka, suggested that Dogen wrote this waka when he saw an old Buddha statue in an old shrine hall, probably by the roadside. Since the shrine was not cleaned for a long time, the statue was covered with dust and Dogen found a spider's web on its face. Then he remembered the story of Rakei Sennin and imagined a magpie making a nest on the crown of the Buddha's head.
Since a waka is a short poem, it is not possible to describe the situation in detail within the poem. Readers need to or can use their imagination to interpret a waka poem like this.