Tatiyasāriputtakoṭṭhikasutta

Suttapiṭaka · Saṁyuttanikāya · Saḷāyatanavaggasaṁyutta · Vol. 18 · Section 776

[776] On one occasion the Venerable Sāriputta and the Venerable Mahākoṭṭhita were dwelling at Bārāṇasī, in the Deer Park at Isipatana. … The same question (was asked): "Friend, what now is the cause, what is the reason, why this has not been declared by the Blessed One?"

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.