Jarir bin Abdullah (r.a.)
It was the 10th year of the Migration. Makkah had been conquered and Islam had spread to more places. The surrounding tribes came to Madinah in groups and became Muslims. The saving hand of Islam also reached Sons of Bajila. They were on the way to Madinah with a delegation of 150 people. Jarir bin Abdullah was the leader of this group. When the group approached Madinah, the Prophet (pbuh) was talking to his Companions. At one point, he said, a Yemeni will come from that door soon. There is a sign of a king and angel on his face. The Companions started to wait for that person with both ears and eyes. Hz. Jarir himself narrates what happened after that as follows:
"As soon as I arrived in Madinah, I changed my clothes and entered the mosque. The Messenger of Allah was talking to his Companions then. I greeted them and sat down. The Muslims were glancing at me. I asked the person sitting next to me, 'Did the Messenger of Allah mention me?' 'Yes,' he said, "He has just mentioned you in a nice way." When I heard that, I praised Allah Almighty. A little later, the Messenger of Allah asked me, 'O Jarir! Why did you come?' I said, 'O Messenger of Allah! I want to be a Muslim in your presence.' I told him that I would pay allegiance to him as a Muslim and asked him to lay any conditions he wished. He said,
‘Pay allegiance to me that there is no god but Allah, that I am the Messenger of Allah, that you will worship Allah without associating any partners with Him, that you will perform prayers and fasting, that you will help Muslims, that you will obey your amir (leader) even if he is an Abyssinian slave and that you will leave the polytheists.’
I said, 'I will.' The Messenger of Allah extended his hand, and I paid allegiance to him regarding the issues he mentioned."
After Jarir, those who were with him became Muslims by paying allegiance one by one. 
Jarir bin Abdullah had a different place in the eye of the Prophet. He complimented Jarir by saying, "Jarir is from us, from Ahl al-Bayt." . He always allowed Jarir to enter into his presence and go out. Whenever he saw Jarir, he would smile. When delegations entered into his presence, he would send a message to Jarir, and he would come wearing nice clothes. The Prophet would introduce him to the delegation and mention his service to Islam proudly.
Once, the Prophet was sitting with his Companions. Meanwhile, Jarir arrived. Somehow, nobody showed him a place to sit. The Prophet (pbuh) looked at his left and right. He looked for a place for him to sit. When he could not find a place, he took of his robe and said to Jarir, "Sit on this." Hz. Jarir took the robe, folded it and kissed; then, he returned it to the Messenger of Allah. He expressed his gratitude by saying, "May Allah treat you as you treated me." The Prophet said to his Companions, "When the leader of a tribe comes to you, treat him as he deserves." 
Hz. Jarir stayed with the Messenger of Allah in Madinah for a while. During this time, he learned a lot from the Messenger of Allah. When he returned to his hometown, he invited his people to Islam. He became a means of guidance for many people. At the same time, he occasionally went to Madinah to listen to the Messenger of Allah. Once, he was in Madinah again. The Prophet asked him what the condition of his tribe was. Jarir gave the good news to the Prophet, "O Messenger of Allah! Almighty Allah made Islam superior. Adhans are called in the mosques and areas of Sons of Balija. The tribes demolished the idols they had worshipped."
The Messenger of Allah was very happy to hear it. However, he asked, "What happened to Dhul-Khalasa?" When Jarir told him that it remained as it was, the Messenger of Allah felt sad. "By Allah! I will get rid of it too. O Jarir! Can you not save me from it? Can you not relieve me?"
Dhul-Khalasa was a temple in Yemen. It was called "Yemen's Kaaba". In this temple was an obelisk made of marble and embroidered with a stone crown. It was between Yemen and Makkah, about seven days away from Makkah. People sacrificed animals for it and showed great respect to it. In this respect, Hz. Jarir's mission was difficult. However, this great man devoted his life to the way of the Messenger of Allah. He was ready to fulfill all of his commands and wishes. He did not think about the difficulties he would face while doing this. He answered without hesitation, "O Messenger of Allah! I will definitely do it." He made preparations without losing time. He took 150 mujahids with him.
Hz. Jarir could not remain on horseback for a long time. Before he left, he said, "O Messenger of Allah! I cannot remain on horseback for a long time." The Prophet patted Jarir on the chest with his blessed hand. Then he said, "O Allah! Make him stable on horseback. Show him the right way. Make him among those who show the right way." After that, Hz. Jarir never fell of the horse.
When Jarir bin Abdullah arrived at Dhul-Khalasa, they did not allow him to demolish it. A battle took place. 200 polytheists were killed. Then the temple was demolished and burned. It was ruined in a short time. Fulfilling his duty successfully, Hz. Jarir returned to Madinah. He gave the good news to the Messenger of Allah. The Messenger of Allah prayed for them. 
After the Farewell Hajj, the Prophet sent Jarir to Yemen to invite Dhul-Kala and Dhu Amr to Islam. Hz. Jarir managed to do it too. He caused both of them to become Muslims. However, in the meantime, he heard that the Messenger of Allah passed away. He became very sad.
Hz. Jarir continued to convey the message of Islam and to teach it in the Era of the Four Caliphs. Hz. Umar admired him and complimented him due to the beauty of his face by saying, "Jarir bin Abdullah is the Yusuf (Joseph) of this ummah." One day, Hz. Umar was sitting with a group of Muslims including Jarir. He caught a bad smell. He said, "Whoever caused that smell should go and make wudu." Hz. Jarir did not want a Muslim to be embarrassed among his friends. He asked, "O leader of the believers! Would it not be better if everybody made wudu?" Somehow, Hz. Umar had not thought of it. He liked his proposal. He complimented Jarir by saying, "May Allah give you a long life! You were wise before being a Muslim; and you are wise now."
Jarir did not hesitate to give advice to people especially to administrators. He regarded the truth superior to everything and did not hesitate to tell the truth. Once, he wrote a letter to Muawiya and reminded him of the following hadith of the Prophet: "Allah will not show mercy to a person who does not show mercy to others." 
The Prophet (pbuh) advised Jarir not to deceive in trade, to tell everyone the truth and to give advice to people. Hz. Jarir acted in accordance with this advice throughout his life. When he sold something, he would inform the customer about all of the defects of it: "This is the commodity; this is the price; these are its defects. You are free to buy it or not." They said to him, "You cannot earn anything if you do like that." He said, "I promised the Messenger of Allah like that. I will not break my promise whether I earn money or not."
Jarir, who spent his entire life in service to Islam and died in the 51 H, narrated many hadiths. Two of them are as follows:
"Do not become like unbelievers who kill one another after my death." 
“If a person starts a good thing in Islam, he receives thawabs like those who do the same thing, without any decrease in their thawabs. If a person starts a bad thing, he receives sins like those who do the same thing, without any decrease in their sins.” 
Musnad, 4: 357; Tabaqat, 1: 347.
Musnad, 4: 358; Faydul-Qadir, 3: 345.
Hayatus-Sahaba, 2: 282.
Tabaqat, 1: 347-348; Musnad, 4: 360.
Musnad, 4: 361.
ibid, 4: 358.
ibid, 4: 357.