Salaam everyone, Why did Muhammad (s) make a surprise attack on Banu Mustaliq. In books of sirah, it says Banu Mustaliq were preparing to make an attack, but I don't trust books of sirah. Please can someone provide me a sahih/hasan hadith or a commentary on hadith (e.g. An-Nawawi, Ibn Hajar) on the reason behind the attack on Banu Mustaliq
The answer to your question can be found here:-
The following are the most important reasons behind this Battle
A- The tribe of Banu Al-Mustaliq supported Quraysh and joined it during the Battle of Uhud against the Muslims. It was among the block of Ahaabeesh tribes who participated in the battle supporting Quraysh.
B- The tribe of Banu Al-Mustaliq governed the main road leading to Makkah. It was a strong barrier that prevented the Muslims from reaching Makkah.
C- News came to the Messenger of Allah sallallaahu
alayhi wa sallam ( may Allah exalt his mention ) that Banu Al-Mustaliq were mobilizing an army to fight him under the leadership of Al-Haarith bin Abi Dhiraar. Having heard about that, the Messenger of Allah sallallaahu alayhi wa sallam ( may Allah exalt his mention ) set out and met them in one of their watering areas called Al-Muraysee‘ in the direction from Qadeed to the sea coast. The Prophet sallallaahu `alayhi wa sallam ( may Allah exalt his mention ) made them taste a bitter defeat there.
Assalamualaikum waramatullahi wabarakatuhu
Actually, the surprise attack was done to Banu mustaliq and the reason was, prophet Muhammad SAW hear that they are preparing to attack Muslim, and with reference with the following Hadith
Ibn 'Aun reported : I wrote to Nafi' inquiring from him whether it was necessary to extend (to the disbelievers) an invitation to accept (Islam) before engaging them in fight. He wrote (in reply) to me that it was necessary in the early days of Islam. The Messenger of Allah (may peace be upon him) made a raid upon Banu Mustaliq while they were unaware and their cattle were having a drink at the water. He killed those who fought and imprisoned others."Sahih Muslim vol.3 book 17 no.4292 p.942.
Mohammed led a surprise attack on the Banu al-Mustaliq tribe while they were inattentive and their cattle were drinking water. That was when Juwairiyyah bint al-Harith was obtained. [as Mohammed's wife]" Abu Dawud vol.2 no.227 p.727-728
Jazakumul llahu khayran