Catutthasāriputtakoṭṭhikasutta

Suttapiṭaka · Saṁyuttanikāya · Saḷāyatanavaggasaṁyutta · Vol. 18 · Section 783

[783] "Friend, for one who does not delight in existence (bhava), who does not take pleasure in existence, who does not rejoice in existence, and who knows and sees the cessation of existence as it really is, the thought 'the Tathāgata exists after death' does not occur … the thought 'the Tathāgata neither exists nor does not exist after death' does not occur. This too, friend, is a reason (pariyāya) why this was left undeclared by the Blessed One."

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.

This passage also appears in 1 other place

Vol. 18 · Section 772 — Paṭhamasāriputtakoṭṭhikasutta