Sunan an-Nasa'i 5025
سنن النسائي#5025SahihIt was narrated from Abu Hurairah that :The Prophet [SAW] said: "Whoever stands (in the voluntary night prayer of) Ramadan out of faith and in hope of reward, his previous sins will be forgiven
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahSahih
Al-AlbaniSahih
Zubair Ali ZaiHasan
In-book reference: 47:41