Let me ask of the gate of Chan: seekers past counting, yet again and again they grow old in vain at the road's end.

The chapter opens by needling the reader. Countless people have tried this, the lyric says, and most of them simply got old. 禪關 is the barrier-gate of Chan practice — a checkpoint you have to get through, not a door standing open. 參求 (cān qiú) is the seeking done in meditation; 參 is cān here, not shēn. Effort on its own, untouched by insight, buys nothing but grey hair.

Grinding a brick to make a mirror, hoarding snow for grain — how many of the young have these delusions led astray!

Two pictures of effort spent on the wrong thing. 磨磚作鏡, grinding a brick to make a mirror, is a Chan teaching case — the kind Japanese Zen calls a kōan — recording an exchange between Nányuè Huáiràng and Mǎzǔ: the master sat rubbing a roof-tile beside his meditating pupil and said he was making a mirror. You can no more sit your way to buddhahood than polish a brick into glass. 積雪為糧, hoarding snow for grain, makes the same point about hardship that feeds nobody. 年少 is nián shào, the young.

A single hair swallows the vast ocean; a mustard seed holds Mount Sumeru — at this the golden-hued ascetic faintly smiles.

A hair drinks the ocean and a mustard seed swallows a mountain — the Huayan idea that the largest thing sits inside the smallest, with neither having to shrink or grow. 須彌, Sumeru, is the mountain at the axis of the world. The 金色頭陀, the golden ascetic, is Mahākāśyapa, master of the dhūta austerities and heir to the teaching handed on without words. His smile is the one he gave at the Flower Sermon, when the Buddha held up a blossom, said nothing, and only Kāśyapa understood.

In the instant of waking one leaps past the ten stages and three vehicles; in stagnation one stays mired in the four births and six paths.

Wake, and you skip the whole syllabus; stall, and you stay in the system. 十地 are the ten stages, the bhūmi, that a bodhisattva climbs, and 三乘 (sān shèng) the three vehicles that carry him. 四生 names the four ways a creature can be born — from a womb, an egg, damp, or sheer transformation — and 六道 the six roads it can be reborn onto. Put together they are the whole revolving wheel of saṃsāra.

Who has heard, before the Cliff of Severed Thought, beneath the Shadowless Tree, the cuckoo's one cry at the dawn of spring?

Cliff of Severed Thought, Shadowless Tree: 絕想崖 and 無陰樹 are not places on any map but Chan names for a mind past the reach of its own ideas, where nothing casts a shadow because nothing stands in the light. 杜宇 is the cuckoo, the bird whose call means spring has arrived — one note at first light, and the long night is over.

The road to Caoxi is steep, the clouds over Vulture Peak are deep; here the voices of old companions fade and are lost.

Two addresses, one Chinese and one Indian. 曹溪, Caoxi, is where the Sixth Patriarch Huìnéng taught; 鷲嶺, Vulture Peak (Gṛdhrakūṭa), is where Śākyamuni preached the Lotus. Naming them in one breath sets the southern Chan line beside the Indian source it claims descent from. The point of the line is that the road to both has gone quiet and hard to find.

On the thousand-zhàng cliff of ice the five-petalled lotus opens; in the ancient hall the curtain hangs and incense curls.

The images turn from hardship to something calmer — ice, a flower, a curtain, incense climbing. 五葉蓮, the five-petalled lotus, picks up Bodhidharma's prophecy 一花開五葉: one flower opening five petals, the five houses that Chan would later divide into. 千丈 is a thousand zhàng, a zhàng being roughly three metres — so, unthinkably high.

At that moment, seeing through to the very source, you shall behold the Dragon King and the Three Treasures.

識破源流 is to see clean through to where the mind starts. 三寶 are the Three Treasures, or Three Jewels — the Buddha, the Dharma he taught, and the Saṅgha, the community that keeps it — and the 龍王, the Dragon King, stands over them as guard. The lyric ends where the chapter begins: what you are after is seeing, not straining.