REPUBLIKA.CO.ID, MEDINA -- There are a number of virtues and historic events in Islam that took place on Monday.
In a Shahih hadith narrated by Muslims, from Abu Qatadah RA, it is said that the Prophet was once asked by a friend, “O Messenger of Allah, why do you fast on Mondays and Thursdays?” The Prophet replied, “That day is the day I was born, the day I was sent, and on that day a revelation was revealed to me” (transmitted by Muslim).
In another Shahih hadith also narrated by Muslims from Abu Hurairah, the Prophet (peace and blessings be upon him) said, “The doors of Paradise are open on Mondays and Thursdays. Then all servants who do not associate God with anything will be forgiven of their sins, except for someone between whom there is enmity between him and his brother. Then it is said, 'Respect the forgiveness of these two men until they are reconciled, postpone the forgiveness of these two until they are reconciled, seek forgiveness of this person until the two are reconciled, '(transmitted by Muslim).
The Prophet (peace and blessings of Allaah be upon him) said: “The deeds of men are checked before Allah twice every week, namely on Monday and Thursday. Then all the faithful servants were forgiven their sins, except for one servant between him and his brother,” (transmitted by Muslim).
Aisha RA said, “The Messenger of Allah used to choose fasting on Mondays and Thursdays,” (transmitted by Nasai and Ibn Majah).
This is also narrated by Abu Hurairah RA, in which the Messenger of Allah (SAW) said, “Various practices are faced (to Allah) on Mondays and Thursdays, so I like it if my practices are confronted while I am fasting,” (transmitted by Tirmidzi).
As for the way Monday and Thursday fasting is basically the same as fasting in general. However, fasting on Monday is a separate practice, as is fasting on Thursday. Thus, the Prophet did not require fasting to be performed on Mondays and Thursdays and should not miss any of these days.