首楞嚴義疏注經 10.152

10.152

不識教相，得此四禪及欲界定少分安樂，便計涅槃。執有漏天作無為解者，因修正定，忽發此禪得少輕安，非是究竟，便妄執計以為涅槃。

Not knowing the doctrinal marks, upon obtaining a minor portion of tranquility and bliss in these four dhyānas and the desire-realm samādhi, he immediately calculates it as nirvāṇa. Clinging to the defiled heavens and interpreting them as unconditioned: due to cultivating correct samādhi, these dhyānas suddenly arise and he obtains a little pliancy; although it is not ultimate, he falsely clings to and calculates it as nirvāṇa.