Musnad Ishaq

Benefits:
In the aforementioned hadith, the twelve rak‘ahs that are mentioned are the emphasized Sunnah (sunnah mu’akkadah) which are performed before and after the obligatory (fard) prayers. These are the ones upon which the Noble Prophet (sallallahu alayhi wa sallam) maintained regularity except during travel. It is narrated from Sayyidah A’ishah (radi Allahu anha) that the Messenger of Allah (sallallahu alayhi wa sallam) said: “Whoever consistently performs twelve rak‘ahs of Sunnah prayers, a house will be built for him in Paradise: four rak‘ahs before Zuhr, two rak‘ahs after Zuhr, two rak‘ahs after Maghrib, two rak‘ahs after ‘Isha, and two rak‘ahs before Fajr.” (Sunan Ibn Majah, Chapters on the Establishment of Prayers and the Sunnah Regarding Them, No. 1140)

In the narration of Sayyiduna Ibn ‘Umar (radi Allahu anhuma), it is mentioned that the Messenger of Allah (sallallahu alayhi wa sallam) used to perform two rak‘ahs before Zuhr. The scholars have reconciled these narrations by stating that sometimes the Prophet (sallallahu alayhi wa sallam) would perform two rak‘ahs before Zuhr and at other times four rak‘ahs. Therefore, both ways are permissible and correct. (Fath al-Bari: 3/377)