Scholars have differed regarding whether or not voluntary prayers are included in the virtue of prayers being regarded as multiplied in reward when offered in the Prophet’s mosque or the Sacred Mosque in Makkah. This is despite the hadeeth of the Prophet ﷺ talking about his mosque,
“The best prayer is the prayer a person offers at home except for the compulsory prayer.” (Bukhaary 731; also see Abu Daawood 1044)
Therefore, prayer at home is better than prayer at the Sacred Precinct or the Prophet’s Mosque, although prayer at a person’s house in Madeenah is not multiplied as opposed to prayer in Makkah. Based on this, many scholars argued that voluntary prayer is not multiplied in terms of spiritual reward. Indeed, it is better than any other place, but not to the extent mentioned in the hadeeth as 100,000 times in the Sacred Masjid and 1,000 times in the Prophet’s Mosque. This only applies to the compulsory prayers. Although the words in the hadeeth are general, if they are placed together with the two hadeeths,
“Prayer in my mosque is better by 1,000 prayers than any other mosque except for the Kaaba!” (Bukhaary 1190)
and
“The best prayer is the prayer a person offers at home except for the compulsory prayer.”,
it becomes clear that prayer in Madeenah is not the same as prayer in Makkah. This leads us to conclude that the multiplicity of the aforementioned reward does not apply to voluntary prayers. This is the opinion of most scholars.
Clarification of the evidence: The evidence is that the Prophet ﷺ said about prayer in his mosque,
“Prayer in my mosque is better by 1,000 prayers than any other mosque except for the Ka’bah!”
and he said,
“The best prayer is the prayer a person offers at home except for the compulsory prayer.”
despite being in Madeenah. This, therefore, indicates that voluntary prayer at home in Madeenah is better than prayer at the Prophet’s Mosque, and prayer at home is never subjected to being multiplied in reward. This is because the Prophet ﷺ said,
“Prayer in my mosque…”
and what he said regarding prayer at the Ka’bah,
“Prayer at the Sacred Precinct is better than 100,000 prayers elsewhere.”
(Ibn Maajah 1406)
Most scholars regarded the entire city of Makkah as the ‘Scared Precinct’, so that is different. Does the phrase of the Prophet, ‘in my mosque’ include all homes? No, it does not, especially when prayer at one’s ‘home’ is better. Therefore, a voluntary prayer, which does not multiply in reward, is not included in Prophet’s ﷺ words,
“Prayer in my mosque…”
The way to understand these hadeeths is to say that the multiplication of reward is only specific to the compulsory prayer which the Prophet ﷺ would pray in his mosque. As for the question about observing the Sunnah prayers offered before and/or after compulsory prayers at the Sacred Precinct when a person is a traveler, it is recorded that Ibn ‘Umar (may Allaah’s Pleasure be upon him and his father), ‘If I offered my voluntary prayer, it would have completed my prayer.’ (Muslim, 689). This means, while he was a resident. In any case, a person should offer as many voluntary prayers as he can. Regarding the Sunnah prayers before and after compulsory prayers, there is debate among scholars. Many scholars argue these Sunnah prayers should not be offered during travel. This is because a traveler is rewarded for the deeds he usually does whilst in the state of residence. Therefore, if he observes his Sunnah prayers when he is resident, he will be rewarded for them when he is travelling.