法身 is the teaching-body, and Yunmen answers the question about it with a concrete act, 六不收. Blyth prints the untranslated Sanskrit “the Dharmakaya” and then imports a three-body Trikaya doctrine the entry's own reading excludes.

The confrontation

R. H. Blyth

A monk asked Ummon, “What is the Dharmakaya?” Ummon answered, “The Six can't get hold of it.”

Zen and Zen Classics, Volume 2: A History of Zen, Hokuseido Press, Tokyo, 1964, p. 118

The canonical source

作麼生是法身。師云。六不收

What is the teaching-body? The master said: the Six cannot take it in.

Yunmen on the teaching-body (法身) · ReadZen · T47n1988 0558a15

法身 the teaching-body 六不收 the Six cannot take it in

And where he construes the word, it leaves the band further

The Dharmakaya is the first of The Trikaya, The Three-fold Body of Buddha. (p. 118)
The Dharmakaya is the highest, the most spiritual of all. (p. 118)

The dictionary's band

Attested band verbatim from the dictionary entry 法身

  • teaching-body
  • body of the teaching
  • teaching body

Entry Explanation (verbatim)

The teaching-body is a corpus-defined body or person-shaped referent whose predicates vary across direct explanations rather than collapsing to an imported glossary formula.

Blyth knew better

Blyth knew better

the Pure Dharma Body

Zen and Zen Classics, Volume 2: A History of Zen, p. 143

Twenty-five pages on, Blyth englishes the very graph: for 清淨法身 he writes “the Pure Dharma Body” (p.143). His own index then splits the two into separate headings, “Dharma Body, 143” and “Dharmakaya, 48, 118.” He had the English rendering in his own hand and chose the Sanskrit for the koan line.

The literal reading

A monk asks Yunmen what the 法身 is, and Yunmen answers 六不收, the Six cannot take it in, a concrete refusal that turns the questioner back from a doctrine to the thing itself. The dictionary attests 法身 in English as the teaching-body, and its Explanation is pointed: the referent's predicates vary across direct answers rather than collapsing into an imported glossary formula. The word is English-able, and the entry warns against exactly the move a glossary makes.

The alteration

Blyth makes both moves the entry warns against. He prints the untranslated Sanskrit “Dharmakaya” where the dictionary attests the English teaching-body, and then he supplies the imported glossary the entry's own reading excludes: the Dharmakaya as first of a three-body Trikaya, the essential nature of Buddha, the highest and most spiritual of the three. Yunmen's answer, 六不收, is a concrete act that refuses precisely this scholastic elaboration; Blyth answers it with the scholasticism. The transliteration falls outside the band, and the Trikaya frame reads into the word a doctrine the koan was declining to give. The self-conviction is in his own index.