Dear Dhamma teachers and scholars,

I came across the following quoted words and translation:

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Kâyamunim vâcâmunim,
manomunimanâsavam,
munim moneyyasampannam.
Âhu ninhâtapâpakam.

Silenced in body, silenced in speech,
silenced in mind, without defilement,
blessed with silence is the sage.
He is truly washed of all evil.
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could someone give me a reference and also explain what is meant
by "Silenced in the body". The only bodily silence I know of is that
of a corpse. surely, the buddha could not have meant that, nor
does he seem to be referring to a body motionless in meditation...

Thanks & metta,
PG