This month is regarded as one of the four sacred months in Islam in which battles are prohibited. The pre-Islamic Arabs also considered warfare blasphemous during the four months.
The month is also a prelude to the month of Ramadan, which follows after the intervening month of Sha'ban. Therefore, when Prophet Muhammad sighted the moon of Rajab, he used to pray to Allah in the following words:
اللّهمّ بارك لنا في رجب و شعبان وبلّغنا رمضان
Allāhumm-a bārik lanā fī rajab-a wa shaʻbān-a wa balligh-nā shahra ramaḍān-a
"O Allah, make the months of Rajab and Sha'ban blessed for us, and let us reach the month of Ramadan (i.e. prolong our life up to Ramadan, so that we may benefit from its merits and blessings)."
The Islamic calendar is a lunar calendar, and months begin when the first crescent of a new moon is sighted. Since the Islamic lunar calendar year is 11 to 12 days shorter than the solar year, Rajab migrates throughout the seasons. The estimated start and end dates for Rajab are as follows (based on the Umm al-Qura calendar of Saudi Arabia):
|AH||First day (CE / AD)||Last day (CE / AD)|
|1431||13 June 2010||12 July 2010|
|1432||3 June 2011||1 July 2011|
|1433||22 May 2012||20 June 2012|
|1434||11 May 2013||9 June 2013|
|1435||30 April 2014||29 May 2014|
|1436||20 April 2015||18 May 2015|
|1437||8 April 2016||7 May 2016|
|1438||29 March 2017||27 April 2017|
|1439||18 March 2018||16 April 2018|
|1440||8 March 2019||6 April 2019|
|1441||25 February 2020||25 March 2020|
|Rajab dates between 2010 and 2020|
Islamic Events 
- 01 Rajab Prophet Muhammad was put in to the womb of his mother.
- 01 Rajab, birth of Shī‘ah Imām, Muhammad al-Bāqir
- 03 Rajab, death of Twelver Imām, ‘Alī al-Naqī
- 05 Rajab, birth of Twelver Imām, ‘Alī al-Naqī
- 06 Rajab, Many Sufi followers of the Chishti tariqa (path) celebrate the anniversary of Khawaja Moinuddin Chishti
- 07 Rajab, Twelvers observe the Festival of Imam Musa al-Kazim in dedication of Musā' al-Kādhim.
- 09 Rajab, birth of ‘Alī al-Asghar
- 10 Rajab, birth of Twelver Imām, Muhammad al-Taqī
- 13 Rajab, birth of ‘Alī ibn Abī Tālib
- 16 Rajab, birth of Gulam Ghous Qadri Sadik shah baba [sufi sant of pashan, in maharashtra state in India]
- 18 Rajab, death of Abraham (In accordance with Shi'a Islam)
- 20 Rajab, birth of Janabe Sakina bint Hussain
- 22 Rajab, Koonday (table cloth dinner) is organized by Shia and Sunni (Not all, as it is controversial) among Muslims of South Asia. It is an occasion for Muslims to discuss Allah and the Ahlul Bayt and to strengthen ties among the community with love and compassion. It is reported to be a practice instructed by 6th Imam, Ja‘far as-Sādiq. It is purported to be the day Mu'āwiyah died;.
- 24 Rajab, victory to Muslims in the Battle of Khaybar
- 25 Rajab, death of Twelver Imām, Musā' al-Kādhim
- 27 Rajab, some Sufi Muslims, along with Shī‘ah Muslims observe the Mi'raj (the day Muhammad (S.A.W) is believed to have ascended to heaven). It is a national holiday in some Muslim countries.
- 28 Rajab, Husayn ibn ‘Alī started his journey to Karbalā from Medina.
- 28 Rajab 1342 A.H. (3 March 1924), the Ottoman Caliphate was abolished by Mustafa Kemal Atatürk
- In the year 5 A.H Bilal ibn al-Harith is reported to have brought a congregation of four hundred men named Banu Muzeena in the presence of Muhammad (S.A.W). They all embraced Islam.
- The Battle of Tabouk took place in Rajab, 9 A.H. (October 630)
- The second Oath of Aqabah took place in Rajab, 12 A.H. (September 633)
- Jerusalem was captured by Saladin in the month of Rajab, 583 A.H. (September/October 1187)
- Nakba Day on 6 Rajab 1367 A.H. (15 May 1948)
- Islamic-Western Calendar Converter (Based on the Arithmetical or Tabular Calendar)
- Islamic Calendar / Hijri Calendar for Makkah
- Conversion of Islamic and Christian dates (Dual)
- Monthly Profiles of the Islamic Calendar(Copyright)
- The Night Journey: The Spiritual Significance of Isra and Mi`raj