After Muhammad had preached publicly for more than a decade, the opposition to him reached such a high pitch that, fearful for their safety, he sent some of his supporters to Ethiopia, where the Christian ruler extended protection to them, the memory of which has been cherished by Muslims ever since. But in Makkah the pursuit worsened. At last, therefore, Muhammad sent seventy of his followers off to the northern town of Yathrib, which was later to be renamed Madina (“The City”). Later, in the early fall of 622, with his closest friend, Abu Bakr al-Siddiq, set off to join the emigrants.