The First Blood Shed for the Cause of Islam

Muhammed bin Ishaaq (rahimahullah) narrates:

In the beginning of Islam, the Sahaabah of Rasulullah (sallallahu ‘alaihi wasallam) would perform salaah in secret. They used to go to the valleys of Makkah Mukarramah to perform salaah so that their Salaah remain hidden from the disbelievers (and so that they be saved from the persecution of the disbelievers).

Once, while Hazrat Sa’d (radhiyallahu ‘anhu) was present with a group of Sahaabah (radhiyallahu ‘anhum) performing salaah in one of the valleys of Makkah Mukarramah, a group of disbelievers caught sight of them. The disbelievers then began to condemn them and criticize their Deen, untill a fight broke out between the two groups (i.e. the Sahaabah (radhiyallahu ‘anhum) and the disbelievers). During this fight, Hazrat Sa’d (radhiyallahu ‘anhu) inflicted a severe head wound to one of the disbelievers by striking his skull with the jaw bone of a camel. This was the first fight (which took place from the beginning of Islam wherein the Sahaabah (radhiyallahu ‘anhum) caused physical injury to the kuffaar and it was the fight fight) in which blood was shed for the cause of Islam. (Usdul Ghaabah 2/308)