Musnad Abu Ya'la al-Mawsili 111:67

Abdullah ibn Umar ibn Aban narrated to us, Abd al-Rahman narrated to us, from Ash'ath, from Ikrimah, from Ibn Abbas, who said: Damrah ibn Jundub went out from his house as a migrant. He said to his family, "Carry me and take me out from the land of the polytheists to the Messenger of Allah, may Allah bless him and grant him peace." He died on the road before he reached the Prophet, may Allah bless him and grant him peace. Then the revelation descended: "And whoever leaves his home as an emigrant to Allah and His Messenger and then death overtakes him, his reward has already become incumbent upon Allah. And Allah is Ever Forgiving, Most Merciful."