Through four beautiful narratives (the People of the Cave; the Man with Two Gardens; Mūsā and Khiḍr; and Dhū al-Qarnayn), this Surah not only summarizes the whole religion of Islam, but also teaches a number of important lessons. Beginning with the role and function of the Prophet Muhammad ﷺ, it goes on to highlight the need for Muslims to show genuine concern for humanity at large.
The importance of genuine knowledge, and the necessity to take it only from qualified teachers who have taqwā, is also highlighted – showing that the highest form of knowledge is that which is acquired through God-consciousness and utter submission to the will of Allah.
The Surah also indicates that believers must always strive against their egos and attribute nothing of the blessings and bounties they possess to their egos or knowhow. One must always remember that Allah is the Master of the whole universe and everything that happens in it is under His control, no matter how good, bad or difficult it might appear.