The Long Āgama Sūtra 7.42

7.42

迦葉答言：「此間百歲，正當忉利天上一日一夜耳，如是亦三十日為一月，十二月為一歲，如是彼天壽千歲。云何，婆羅門！汝親族五戒具足，身壞命終，必生忉利天上。彼生天已，作是念言：『我初生此，當二三日中，娛樂遊戱，然後來下報汝言。』者，寧得見不？」

Kāśyapa answered, “A century here is exactly one day and night in the Trāyastriṃśa Heaven. Thirty days makes one month, and twelve months makes a year there. Thus, those gods live for thousands of years. How is it, priest? That relative you knew who completed the five precepts was surely born up in the Trāyastriṃśa Heaven when their body broke up and their life ended. After being born there, they would have thought, ‘It’s only been two or three days since I was born here. I’ll enjoy it and entertain myself. Afterward, I’ll go down and tell him about it.’ Would they see you?”