The companions of Imam al-Hussayn (peace be upon him) were distinguished by their unique qualities that made them the best martyrs. This small group had a very special relationship with the Imam of their era Aba Abdillah al-Hussayn (peace be upon him) and has positions that demonstrate the depth and rooting of this relationship that is beyond the level of religious onus to reach the state of love and devotion that stemmed from their knowledge of the Imam of their time (peace be upon him).
Among this group of faithful companions; Habib Ibn Mudhahir al Asadi, who was one of the companions of the Prophet (Allah's prayers be upon him and upon his holy Household), resident of Kufa and was one of the followers of Imam Ali the Commander of the Faithful (peace be upon him), and among his close companions and has participated with him in all of his wars.
After the death of Mu'awiya (60/680), Habib and some of the heads of Shi'a communities in Kufa, refused to swear allegiance to Yazid, and sent letters to Imam al-Hussayn (peace be upon him) inviting him to lead Kufa in her uprising against Umayyad Dynasty.
When Muslim Ibn 'Aqeel came to Kufa as the Imam's representative, they rushed to support him. People of Kufa secretly pledged allegiance to Habib and Muslim Ibn 'Awsaja as the representative of Muslim Ibn 'Aqeel. They did all they could in this regard.
But when 'Ubaydullah Ibn Ziyad came to Kufa, he threatened people and launched crackdown against allegiance to Muslim Ibn 'Aqeel; so people abandoned their allegiance to Muslim Ibn 'Aqeel and lift him alone. The tribe of Banu Asad hid Habib and Muslim Ibn 'Awsaja to protect them against Ibn Ziyad's agents. Habib and Muslim Ibn 'Awsaja left Kufa to join Imam al-Hussayn (peace be upon him). They hid themselves from 'Ubaydullah Ibn Ziyad's spies and agents, so they moved at nights and hid during days. Eventually, they joined Imam al-Hussyan's camp in Karbala on Muharram 7th 61AH.
Upon reaching Karbala, Habib repeats his expression of loyalty to Imam al-Hussayn (peace be upon him). As soon as he observed the great number of Imam's enemies and small number of his companions, Habib asked Imam al-Hussayn (peace be upon him) to go to a nearby tribe of Banu Asad and to ask them to join Imam (peace be upon him). With the permission of Imam, Habib hurried to the tribe and started preaching them and encouraging them to join the Imam. However, 'Umar Ibn Sa'd stopped the tribe from joining Imam (peace be upon him) by sending an army to them. And Habib came back alone to the tent of the Imam (peace be upon him) and informed him of what happened.
In the morning of 'Ashura' [tenth day of Muharram], Imam al-Hussayn (peace be upon him) appointed Habib Ibn Mudhahir as the commander of the left wing. He put Zuhayr Ibn Qayn on the right wing and al-Abbas Ibn Ali (peace be upon him) on the center of the army.
While Muslim Ibn 'Awsaja covered in his own blood was breathing his last breaths, Imam al-Hussayn (peace be upon him) and Habib came to him and Imam prayed to God to bless his soul. Then Imam read the verse of Qur'an which says, "Among the faithful are men who fulfill what they have pledged to Allah. Of them are some who have fulfilled their pledge, and of them are some who still wait, and they have not changed in the least." (33:23) Then Habib told him, "Your death is very hard for me, but I give you the good news of Paradise." Muslim Ibn 'Awsaja in return said with a weak voice, "May God give you good news." Habib said, "If my martyrdom were not close, I would have liked you to tell me your will [so that I executed for you] and by that I have fulfilled my tribal and religious duty toward you." Muslim Ibn 'Awsaja pointed to Imam al-Hussayn (peace be upon him) and told Habib, "My will is to stay with Imam al-Hussayn (peace be upon him). May God bless you, keep defending him as long as you are alive, and do not stop supporting him until you are killed." Habib said, "I will execute your will and I will make you happy."
At noon of 'Ashura', when Abu Thumama al-Sa’idi reminded Imam of the time of the prayer, Imam told his companions to ask the enemy to stop the war so that they can pray. Hosayn Ibn Numayr (Hosayn Ibn Tamim) said, "Your prayers won't be accepted by God."
"You think that the prayer of Prophet's household will not be accepted" replied Habib, "Your prayers will not be accepted, you drunk (donkey)!" Then Habib attacked him and hit his horse on the face with the sword. He fell to the ground and his friends came to help and rescued him from Habib's attack.
Despite being very old, Habib fought like a hero and killed 62 people of the enemy. Just then, Budayl Ibn Maryam 'Aqfani attacked him and hit him on the head with his sword. Another enemy hit him with a spear, causing him to fall off the horse and down to the ground. Then, Budayl Ibn Maryam beheaded him. Habib had an underage son named Qassim, who killed Budayl after he came of age.
Imam al-Hussayn (peace be upon him) came to him and said: "I expect from God [the reward of] myself and my supportive companions."
Habib (peace be upon him) was then seventy five years old.