and Allah said "And proclaim the pilgramage among men; they will come to thee on foot and on every kind of camel. Lean on account of Journeys through deep and distant mountain highways" Surah 22 ~ Al Hajj Part 27
After three years of constant but quiet struggle, only thirty followers were secured. An important change now occurred in the relations of the Prophet with the citizens of Mecca (Makkah). His compatriots had begun to doubt his sanity, thinking him crazy or possessed by an evil spirit. Here to he preached quietly and unobtrusively. It was at this juncture that he decided to appeal publicly to the Makkans, requesting them to abandon their idolatry. For this he arranged a gathering on a neighboring hill and there spoke to them of their folly in the sight of Allah in worshipping pieces of stone which they called their gods. He invited them to abandon their old impious worship and adopt the faith of love, truth and purity. He warned them of the fate that had overtaken past races who had not heeded the preaching of former prophets. But the gathering departed without listening to the warning given them by the Prophet.
Having thus failed to induce his fellow citizens to listen to him, he turned his attention to the strangers arriving in the city on commerce or pilgrimage. But the Quraish made attempts to frustrate his efforts. They hastened themselves to meet the strangers first on different routes, to warn them against holding any communication with the Prophet, whom they represented as a dangerous magician. When the pilgrims or traders returned to their homes, they carried with them the news of the advent of the bold preacher who was inviting the Arabs loudly - at the risk of his own life - to abandon the worship of their dear idols.
Now the Prophet and his followers became subject to some persecution and indignity. The hostile Quraish prevented the Prophet from offering his prayers at the Sacred House of the Kabah; they pursued him wherever he went; they covered him and his disciples with dirt and filth when engaged in their devotions; they scattered thorns in the places which he frequented for devotion and meditation. Amidst all these trials the Prophet did not waver. He was full of confidence in his mission, even when on several occasions he was put in imminent danger of losing his life.
At this time Hamza, the youngest son of Abdul Muttalib, adopted Islam. Hamza was a man of distinguished bravery, an intrepid warrior, generous and true, whose heroism earned for him the title of the "Lion of Allah." He became a devoted adherent of Islam and later even lost his life in the cause.
The Prophet continued preaching to the Arabs in a most gentle and reasonable manner. He called the people, so accustomed to sin. wickednes and wrong doings, to abandon their abominations. In burning words which excited the hearts of his hearers, he warned them of the punishment which Allah had inflicted upon the ancient tribes of 'Ad and Thamud who had obstinately disobeyed the teachings of Allah's messengers to them. He adjured them by the wonderful sights of nature, by the noon day brightness, by the night when it spreads its veil, by the day when it appears in glory to listen to his warning before a similar destruction befell them. He spoke to them of the Day of Reckoning, when their deeds in this world will be weighed before the Eternal Judge, when the children who had been buried alive would ask of what crime were they put to death for.
Almighty Allah said: Nay, they wonder that there has come to them as a Warner (Muhammad) from among themselves. So the disbelivers say: "This is a strange thing! When we are dead and have become dust (shall we be resurrected)? That is a far return." We know that which the earth takes of them (their dead bodies), and with Us is a Book preserved (i.e., the Book of Decrees).
Nay, but, they have denied the truth (this Quran) when it has come to them, so they are in a confused state (can not differentiate between right and wrong). Have they not looked at the heaven above them, how We have made it and adorned it, and there are no rifts in it? And the earth! We have spread it out, and set there on mountains standing firm, and have produced there in every kind of lovely growth (plants). An insight and a reminder for every slave turning to Allah (i.e., the one who believes in Allah and performs deeds of His obedience, and always begs His pardon). And We sent down blessed water (rain) from the sky, then we produce therewith gardens and grain (every kind of harvests that are reaped). And tall date palms, with ranged clusters; a provision for (Allah's) slaves. And We give life therewith to a dead land. Thus will be the resurrection (of the dead). Denied before them (i.e. these pagans of Makkah who denied you, O Muhammad) the people of Noah, and the dwellers of Rass, and the Thamud, and 'Ad, and Pharaoh, and the brethren of Lot, and the dwellers of the Wood, and the people of Tubba, everyone of them denied their Messengers, so My Threat took effect." ( 50: 2-14 Quran)