MahāvaggavaggaSabbamatthītikathā

Abhidhammapiṭaka · Kathāvatthu · Vol. 37 · Section 329

[329] [Sakavādin:] "Nibbāna exists; Nibbāna does not abandon the state of being Nibbāna. Is Nibbāna permanent, stable, eternal, not subject to change?" [Paravādin:] "Yes." [Sakavādin:] "The past exists; the past does not abandon the state of being past. Is the past permanent, stable, eternal, not subject to change?" [Paravādin:] "It should not be said so. …"

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.

This passage also appears in 3 other places