He proceeded towards Nejd leading 400-700 men after he had mandated Abu Dhar to manage Madinah during his absence.
[5] When prayer time came, the Muslims worried that the Ghatafan men might descend from their mountain hideout and attack them while they were praying.
And when you journey in the earth, there is no blame on you if you shorten the prayer, if you fear that those who disbelieve will cause you distress, surely the unbelievers are your open enemy.
[5][9] Some scholars claim that the expedition took place in Nejd (a large tableland in the Arabian Peninsula) in Rabi‘ Ath-Thani or Jumada Al-Ula, A.H. 4 (or beginning of AH 5).
They claim that it was strategically necessary to carry out this campaign in order to quell the rebellious Bedouins to prepare for the encounter with the polytheists, i.e. minor Badr Battle in Sha‘ban A.H. 4.
However, Safiur Rahman Mubarakpuri claimed that Dhat Ar-Riqa‘ campaign took place after the fall of Khaibar (and not as part of the Invasion of Nejd).
The rules relating to the prayer of fear that Muhammad observed at Dhat Ar-Riqa‘ campaign, were revealed at the Asfan Invasion.
[Quran 5:11]The event is mentioned by the Muslim jurist Tabari as follows: There is a difference in opinion as to which expedition took place after that against the Banu al-Nadir, according to Ibn Humayd - Salamah - Ibn Ishaq: The Messenger of God remained in Medina after the expedition against the Banu al-Nadir for the two months of Rabi' and part of the month of Jumada (from August 11 to late October, 625 [in the intercalated calendar (which was in use at the time) the corresponding dates are 14 May to late July - see section "Discrepancy in dates" below]).
The Muslim jurist Ibn Qayyim Al-Jawziyya mentions the event in his biography of Muhammad, Zad al-Ma'ad.
In his book Essai sur l'histoire des arabes avant l'islamisme, pendant l'epoque de Mahomet Armand-Pierre Caussin de Perceval equates Ramadan with the Muslim month ending in January AD 624 and notes (correctly) that the seventeenth of that month was a Saturday (14 January).
[11] This period is too long (the average is seven intercalations in nineteen years rather than seven in 21), which means that his dates become progressively more and more late moving back from the reform of the calendar in AD 632.