サヒーフ・アル＝ブハーリー #37
Sahih (Authentic)
Allah's Messenger (ﷺ) said: "Whoever establishes prayers during the nights of Ramadan faithfully out of sincere faith and hoping to attain Allah's rewards (not for showing off), all his past sins will be forgiven
伝承の連鎖（イスナード）
Narrated Abu Huraira