(23) باب فِي اللَّيْلِ سَاعَةٌ مُسْتَجَابٌ فِيهَا الدُّعَاءُ
Jabir said he heard Allah's Messenger (ﷺ) say:
There is an hour during the night in which no Muslim individual will ask Allah for good in this world and the next without His giving it to him; and that applies to every night.
Reference: Sahih Muslim 757 a
In-book reference: Book 6, Hadith 199
USC-MSA web (English) reference(deprecated numbering scheme): Book 4, Hadith 1654