Is it true that whoever prays 12 supererogatory rak'ahs daily (2 before Fajr, 4 before Dhuhr, 2 after Dhuhr, 2 after Maghrib, and 2 after Ishaa') will have a palace built for him in Paradise? And what is the total number of supererogatory prayers in a day, originally? And is it true that the Messenger, peace be upon him, did not exceed 40 rak'ahs in a day and night, and if so, what are those 40 rak'ahs, and if not, how many did he pray?

It is authentically reported in Sahih Muslim that the Prophet, peace and blessings be upon him, said: "There is no servant who prays twelve voluntary rak'ahs to Allah every day, besides the obligatory prayers, except that Allah will build for him a house in Paradise." Their details, as mentioned in the hadith of Umm Habiba, are: "Whoever persists in praying twelve rak'ahs in a day and night will enter Paradise: four rak'ahs before Dhuhr, two rak'ahs after Dhuhr, two rak'ahs after Maghrib, two rak'ahs after Isha, and two rak'ahs before Fajr."

Ibn al-Qayyim mentioned that the Prophet, peace and blessings be upon him, used to consistently pray forty rak'ahs in a day and night: seventeen obligatory, twelve regular voluntary (sunnah ratiba), and eleven rak'ahs for the night prayer (qiyam al-layl). This does not preclude adding more occasionally, as he would pray four or eight rak'ahs for the Dhuha prayer. It has also been authentically reported that he encouraged two rak'ahs before Maghrib and four rak'ahs after Dhuhr: "Whoever maintains four rak'ahs before Dhuhr and four after it, Allah will forbid him from the Hellfire."