We’d like to state that Almighty Allah says, “And keep up prayer in the two parts of the day and in the first hours of the night; surely good deeds take away evil deeds this is a reminder to the mindful.” (Hud: 114)
In their commentary on this verse, Muslim scholars say that the phrase “in the two parts of the day” refers to dawn and sunset prayers, whereas the phrase “in the first hours of the night” refers to night prayer.
However, the claim that the obligatory prayers are only three is baseless. Mentioning these three prayers in the Qur’an is to highlight their importance just like when a father tells his elder son to take care of one of his brothers; it doesn’t mean that he should take care of the mentioned brother and neglect the others. Thus, when Almighty Allah mentions some prayers specifically in the Qur’an, as He does in suratAl-Baqarah (238), this does not mean that only the two mentioned prayers are obligatory while others are not.
Besides, many Hadiths have confirmed that five daily obligatory prayers are ordained on Muslims. When the Prophet (peace and blessings be upon him) sent Mu`adh to Yemen, he said to him, “Invite the people to testify that none has the right to be worshipped but Allah and I am Allah’s Messenger, and if they obey you to do so, then teach them that Allah has enjoined on them five prayers in every day and night (in twenty-four hours), and if they obey you to do so, then teach them that Allah has made it obligatory for them to pay the Zakah from their property and it is to be taken from the wealthy among them and given to the poor.” (Reported by Al-Bukhari)
There is also the well-known hadith reported by al-Bukhari and Muslim explaining how the five daily prayers were ordained on the Night Journey of the Prophet (peace and blessings be upon him) and they were originally fifty prayers and then reduced to five. The Prophet said: “So I returned to Allah and He said, ‘These are five prayers and they are all (equal to) fifty (in reward) for My Word does not change.’”
Imam Muslim reported on the authority of Abu Hurayrah who said: Verily the Messenger of Allah (may peace and blessings be upon him) said: “Performing the five (daily) prayers and from one Friday prayer to the (next) Friday prayer, and from Ramadan to Ramadan are expiations for the (sins) committed in between (their intervals) provided one shuns the major sins.”
All Muslims, in all times, have unanimously agreed that five daily prayers are what Allah enjoined on Muslims.