Full Sharh — Riyad as-Salihin 438

English Translation

'Abdullah bin As-Sa'ib (May Allah be pleased with him) reported:: The Messenger of Allah (ﷺ) used to perform four Rak'ah prayer after the declining of the sun before Zuhr prayer and would say, "This is an hour at which the gates of heaven are opened, and I like that my good deeds should rise to heaven at that time.".