Bara bin Ma’rur (r.a.)
Bara bin Ma'rur was one of the twelve representatives chosen among the participants of the Second Pledge of Aqaba. Hz. Bara spoke as follows when he paid allegiance to the Prophet in Aqaba:
"Praise be to Allah, who honored us with Muhammad and made us beloved. We are not the first to be invited to Allah and His Messenger. However, we are the first to respond. We have heard and obeyed the invitation of Allah and His Messenger. O people of Aws and Khazraj! Allah has honored you with His religion. If you have accepted to listen to and obey willingly, obey Allah and His Messenger.
Praise be to Allah, who sent you with the true religion that we will protect you from the things that we protect ourselves and our families. By Allah, we are people who know how to fight well."
Hz. Bara worked very hard to spread Islam in Madinah. He caused a lot of people to become Muslims.
In the first years of Islam, Muslims used to pray by turning toward Jerusalem. Qiblah had not been changed to the Kaaba yet. This saddened Bara a lot. He desired to pray by turning toward the Kaaba. Once, he even performed a prayer by turning toward the Kaaba on the way to Makkah. The other Companions did not welcome his behavior. When they arrived in Makkah, Hz. Bara asked the Messenger of Allah about it: "O Messenger of Allah! I regarded it appropriate to perform the prayer by turning toward the Kaaba; I did not want the Kaaba to remain behind me. However, my friends oppose me. What would you say about it?" The Messenger of Allah said, "You have a qiblah now. I wish you had been a little patient." Thereupon, Hz. Bara turned toward Jerusalem like other Muslims in prayer after that.
Hz. Bara got sick just before the Messenger of Allah migrated to Madinah. He realized that he could not get rid of this illness. He willed that one third of his wealth be given to the Prophet to spend as he wished, one third be spent in the way of Allah, and one third be left to his children. He died before seeing the Prophet’s migration to Madinah.
Bara had promised the Prophet that he would come to the Kaaba during hajj season. When he got sick, he said, "Turn me toward the Kaaba due to my promise to the Messenger of Allah. For, I promised him that I would come." His relatives did as he wished.
When the Prophet migrated to Madinah, he went to the grave of Bara with the Companions. He performed his janazah prayer there. He said, "O Allah! Forgive him, show him mercy, and be pleased with him!"
Thus, Hz. Bara attained the honor of being the Companion who first turned toward the Kaaba in prayer, buried turning toward the Kaaba for the first time and whose janazah prayer was performed on his grave first.
May Allah be pleased with him! 
Tabaqat, 3: 618-620; Sirah, 2: 82-83.