1- he (pbuh) said: (the best of one’s prayers is that which he performs at home, except obligatory prayers). agreed upon.
2- he (pbuh) said: (man’s voluntary prayer, where people do not see him, is twenty five times as equal as that which he performs publicly). narrated by abu-ya’la, al-albani said it is authentic.
3- he (pbuh) said: (man’s prayer at home surpasses his prayer, where people can see him, as much as the obligatory prayer surpasses the supererogatory one). narrated by at-tabarani, al-albani said it is good.
based upon this, one should repeat this sunnah (the prophet’s tradition), in the arranged sunnahs*, ad-duha (forenoon) prayer and al-watr* several times per day and night, and in each one of them, he should be keen on performing it at home to increase his reward and attain the sunnah.
the fruit of applying these supererogatory prayers at hhome:
a- it is a means to fulfill submissiveness, fidelity and keeping away from hypocrisy.
b- it causes mercy to come down on the house and causes the devil to get out of it.
c- it is a reason for doubling its reward just as the obligatory prayer’s reward is doubled (when performed) in the mosque.
* the arranged sunnahs = the supererogatory prayers performed with the daily five obligatory prayers and according to their order.
* al-watr = a supererogatory prayer performed at the end of the muslim’s daily prayers, whose number of rak’as (units) should be an odd number.