In the Waddan valley which connects Makkah with the outside world, lived the tribe of Ghifar. The Ghifar existed on the meagre offerings of the trade caravans of the Quraysh which plied between Syria and Makkah. It is likely that they also lived by raiding these caravans when they were not given enough to satisfy their needs.
 
Jundub ibn Junadah, nicknamed Abu Tharr, was a member of this tribe. He was known for his courage, his calmness and his far sightedness and also for the repugnance he felt against the idols which his people worshipped. He rejected the silly religious beliefs and the religious corruption in which the Arabs were engaged.

While he was in the Waddan desert, news reached Abu Tharr that a new Prophet had appeared in Makkah. He really hoped that his appearance would help to change the hearts and minds of people and lead them away from the darkness of superstition. Without wasting much time, he called his brother, Anis, and said to him: “Go to Makkah and get whatever news you can of this man who claims that he is a Prophet and that revelation comes to him from the heavens. Listen to some of his sayings and come back and recite them to me.”

Anis went to Makkah and met the Prophet Sallallahu Alyhi Wa Sallam. He listened to what he had to say and returned to the Waddan desert. Abu Tharr met him and anxiously asked for news of the Prophet.

“I have seen a man,” reported Anis, “who calls people to noble qualities and there is no mere poetry in what he says.”
“What do people say about him?” asked Abu Tharr.
“They say he is a magician, a soothsayer and a poet.”
“My curiosity is not satisfied. I am not finished with this matter. Will you look after my family while I go out and examine this prophet’s mission myself?”
“Yes. But beware of the Makkans.”

On his arrival at Makkah, Abu Tharr immediately felt very apprehensive and he decided to exercise great caution. The Quraysh were noticeably angry over the denunciation of their gods. Abu Tharr heard of the terrible violence they were meting out to the followers of the Prophet but this was what he expected. He therefore refrained from asking anyone about Muhammad not knowing whether that person might be a follower or an enemy.

At nightfall, he lay down in the Sacred Masjid. Ali ibn Abi Talib passed by him and, realising that he was a stranger, asked him to come to his house. Abu Tharr spent the night with him and in the morning took his water pouch and his bag containing provisions and returned to the Masjid. He had asked no questions and no questions were asked of him.

On the third night, however, Ali asked him, “Aren’t you going to tell me why you came to Makkah?” “Only if you will give me an undertaking that you will guide me to what I seek.” Ali agreed and Abu Tharr said: “I came to Makkah from a distant place seeking a meeting with the new Prophet and to listen to some of what he has to say.”

Ali’s face lit up with happiness as he said, “By Allah, he is really the Messenger of Allah,” and he went on telling Abu Tharr more about the Prophet Sallallahu Alyhi Wa Sallam and his teaching. Finally, he said: “When we get up in the morning, follow me wherever I go. If I see anything which I am afraid of for your sake, I would stop as if to pass water. If I continue, follow me until you enter where I enter.”

Abu Tharr did not sleep a wink the rest of that night because of his intense longing to see the Prophet and listen to the words of revelation. In the morning, he followed closely in Ali’s footsteps until they were in the presence of the Prophet Sallallahu Alyhi Wa Sallam. “As-salaamu alayka yaa Rasulullah, (Peace be on you, O Messenger of Allah),” greeted Abu Tharr. “Wa alayka salaamullahi wa rahmatuhu wa barakaatuhu (And on you be the peace of Allah, His mercy and His blessings),” replied the Prophet Sallallahu Alyhi Wa Sallam.

Abu Tharr was thus the first person to greet the Prophet Sallallahu Alyhi Wa Sallam with the greeting of Islam. After that, the greeting spread and came into general use.

The Prophet, peace be on him, welcomed Abu Tharr and invited him to Islam. He recited some of the Qur’an for him. Before long, Abu Tharr pronounced the Shahadah, thus entering the new religion (without even leaving his place). He was among the first persons to accept Islam.

In the year 32 AH, the self-denying Abu Dharr passed away. The Prophet, peace be upon him, had said of him: “The earth does not carry nor the heavens cover a man more true and faithful than Abu Tharr.”