The Prophet ﷺ used to pray four units before the afternoon prayer, separating them with the salutation upon the angels brought near, and upon those who follow them from among the Muslims and the believers.
كان النبي ﷺ يصلي قبل العصر أربع ركعات، يفصل بينهن بالتسليم على الملائكة المقربين، ومن تبعهم من المسلمين والمؤمنين.
Tirmidhi narrated it (429) via Sufyan, from Abu Ishaq, from Asim bin Damra, from Ali, and he narrated the hadith. Its isnad is hasan because of the discussion concerning Asim bin Damra, for he is "truthful."Tirmidhi said, "Hasan."Ishaq bin Ibrahim held the view that one should not separate the four units before Asr, and he cited this hadith as evidence. Ishaq said, "The meaning of separating between them with the salutation is, that is, the testimony of faith."Shafii and Ahmad held that the night and day prayers should be performed two by two, and they preferred separating the four units before Asr.Nawawi cited it in Khulasa (1466) and affirmed Tirmidhi's ruling. This is an abridgment concerning the voluntary prayers of the Prophet ﷺ during the day.