3.2.40
वाचि यमो व्रते
Operational rule vidhi
The affix खच् comes after the verb यस् 'to curb' when the word वाक् 'speech' is in composition with it as an object and the sense indicated is that of a vow.
Word by word (padaccheda)
Right context वाचि saptamī · ekavacanaLeft context यमः pañcamī · ekavacanaRight context व्रते saptamī · ekavacana
- Right context Saptamī (7th case): "when X follows", the operation applies to what precedes (1.1.66 तस्मिन्निति निर्दिष्टे पूर्वस्य). Also a condition or domain ("in the sense of").
- Left context Pañcamī (5th case): "after X", the operation applies to what follows (1.1.67 तस्मादित्युत्तरस्य). Also used for limits and sources.
Dotted words are technical terms, dashed ones pratyāhāras (names for classes of sounds or affixes). Hover or tap one to see its card.
Full reading
वाचि यमः व्रते
Pāṇini leaves out words that carry over from earlier sūtras. Expand to see the rule as a reader actually understands it.
Commentary
The affix खच् comes after the verb यस् 'to curb' when the word वाक् 'speech' is in composition with it as an object and the sense indicated is that of a vow.
The word व्रत means a vow taken according to the rules of Dharma sastra. Thus वाचंयम आस्ते 'he has taken the vow of rigid silence'.
Why do we say 'vow'? Otherwise the form is वाग्यामः 'restraining speech' 6.3.69.
Śrīśa Chandra Vasu, The Ashtadhyayi of Panini (1897), via ashtadhyayi.com.