Ali arrived in Yathrib renamed as Madina-tun-Nabi or Madina in the honor of the Holy Prophet towards the close of September in the year 622 C.E. The Holy Prophet welcomed him to Madina, and appreciated his services for risking his life for him at Makkah in facing the fury of the Quraish. The Holy Prophet was glad to note that the task allotted to Ali at Makkah had been properly and satisfactorily done by him.
The world of Madina was quite different from the world of Makkah. At Makkah the Muslims were a persecuted people; at Madina they were the masters of their destiny. At Makkah they were surrounded by enemies; at Madina they were in the midst of friends. The life at Madina marked a break with the past. The days of trials, tribulations and tortures were over and the Muslims were now set on the path of fulfillment. The Muslims were now to build a new society and a new common wealth.
The climate of Makkah was dry, but the climate of Madina was damp. The landscape of Makkah was marked by barren rocks, and stony wastes; the landscape of Madina was market by agricultural fields, gardens, and groves of date palms. The change in the physical scene affected the health of the emigrants, and some of them including Abu Bakr fell sick. Ali withstood the climatic change without being affected in health. He spent most of his time in nursing the sick and helping them in adjusting themselves to the new environments.