Al-Kāfi #1305“I heard abu ‘Abd Allah (a.s.), say, ‘The excellence of prayer, after an obligatory Salah (prayer), over prayers after non-obligatory Salah...
Al-Kāfi #1304“Abu ‘Abd Allah (a.s.), has said, ‘If after completing an obligatory Salah (prayer), one remains in his place for ta‘qib (praying and...