Musnad Ahmad 2:227

Yazid narrated to us, Jarir informed us, Zubayr ibn al-Khirrit informed us, from Abu Labid, who said: A man from Tahiya went out as an emigrant, who was called Bayrah ibn Asad. He arrived in Medina a few days after the death of the Messenger of Allah, may Allah bless him and grant him peace. Umar saw him and knew that he was a stranger, so he said to him, "Who are you?" He said, "From the people of Oman." He said, "From the people of Oman?" He said, "Yes." He took him by the hand and brought him in to Abu Bakr, may Allah be pleased with him, and said, "This is from the people of the land about which I heard the Messenger of Allah, may Allah bless him and grant him peace, say: 'I indeed know a land called Oman, the sea splashes upon its side. In it is a tribe of the Arabs; if my messenger were to come to them, they would not pelt him with an arrow nor a stone.'"