2.3.54
रुजार्थानां भाववचनानामज्वरेः
Operational rule vidhi
The object of verbs having the sense of रुज् 'to afflict', with the exception of the Causative verb ज्वरय 'to be feverish', takes the 6th-Case-affix, when the verb expresses a condition (i.e. when the subject is an Abstract noun).
Word by word (padaccheda)
Target रुज- अर्थानाम् ṣaṣṭhī · bahuvacanaTarget भाव- वचनानाम् ṣaṣṭhī · bahuvacanaTarget अज्वरेः ṣaṣṭhī · ekavacana
- Target Ṣaṣṭhī (6th case): names what gets replaced, "in place of X" (1.1.49 षष्ठी स्थानेयोगा).
Full reading
रुज-
Pāṇini leaves out words that carry over from earlier sūtras. Expand to see the rule as a reader actually understands it.
Commentary
The object of verbs having the sense of रुज् 'to afflict', with the exception of the Causative verb ज्वरय 'to be feverish', takes the 6th-Case-affix, when the verb expresses a condition (i.e. when the subject is an Abstract noun).
Ex. चौरस्य रुजति रोगः 'the disease afflicts the thief' चौरस्यामयति आमयः ।
Why do we say 'when the subject is an Abstract noun'? Observe नदी कूलानि रुजति 'the river breaks the banks.' So also not here चौरं ज्वरयति ज्वरः 'the fever burns the thief.' So also when the verb संताप is used, चौरं संतापयति तापः ।
३
The word शेष is also understood here. Thus चौरं रुजति रोगः ॥
Śrīśa Chandra Vasu, The Ashtadhyayi of Panini (1897), via ashtadhyayi.com.