The people of Mecca wanted to know whether Prophet Muhammad (PBUH) had knowledge of the unknown; so they asked him three questions which were related to the history of Jews and Christians. They inquired about sleepers of the cave, the story of Khidr and about Zul-Qurnain. Allah answered all of these three questions in this surah. Regarding sleepers of the cave, Allah said that they also believed in oneness of God and had to face hardships just like the Muslims of Mecca. Allah further encouraged believers to not to bow down before a cruel society and to migrate to a peaceful land if things get tough. The purpose of narrating the story of Khidr is to console Muslims by telling them that they should have full faith in the wisdom of Allah who knows the unseen. It instructs Muslims not to feel discouraged when things go against them; as in the end wisdom of Allah will bring a favorable outcome for their cause. The story of Zul-Qurnain advises the chiefs of Mecca to learn from Zul-Qarnain who was a great conqueror and a great ruler; he had built a very strong wall for protection but he put his trust in Allah and not in the wall. The Quran further highlights that the chiefs of Mecca were insignificant in size if compared to the ruler Zul-Qurnain.