masculine singular dative (yathārūpāya) + 1st person singular nominative enclitic pronoun (ahaṁ) in a contraction yathārūpāyāhaṁ, often written yathārūpāya-ahaṁ; instrumental-ablative 'in the way that I am' or dative 'to one like me'
Analysis. yathārūpa 'of such a form/nature' + ahaṁ 'I'; yathā (correlative adverb 'in which way, as') + rūpa ('form, nature') + dative ending -āya; the enclitic ahaṁ emphasizes the speaker as the referent of comparison.
Etymology. yathārūpa is a compound of yathā 'as, in the manner that' (correlative adverb, from PIE *yod-tho-, cognate with Latin quot 'how many', Greek hostis 'whoever') and rūpa 'form, appearance, nature' (from PIE *reup- 'to break, shape', cognate with English rupture, Latin rumpere 'break'). The word is often used in doctrinal contexts to mean 'according to nature' or 'in their proper way', particularly in passages about appropriate speech or conduct.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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