Riyad as-Salihin, Book 12, Hadith 1291 (In-Book) ⓘ

Salman (May Allah be pleased with him) reported: I heard the Messenger of Allah as saying, "Observing Ribat in the way of Allah for a day and a night is far better than observing Saum (fasting) for a whole month and standing in Salat (prayer) in all its nights. If a person dies (while performing this duty), he will go on receiving his reward for his meritorious deeds perpetually, and he will be saved from Al- Fattan."[Muslim].

وعن سلمان رضي الله عنه قال‏:‏ سمعت رسول الله صلى الله عليه وسلم يقول‏:‏ ‏ "‏رباط يوم وليلة خير من صيام شهر وقيامه، وإن مات فيه أجري عليه عمله الذي كان يعمل، وأجري عليه رزقه، وأمن الفتان‏" ‏ ‏(‏‏(‏رواه مسلم‏)‏‏)‏‏.‏