Quran

There is a lesson in this and similar verses: the one who is required to call people to Allah must convey the message and strive by all possible means to guide them and block the path of misguidance as much as he can, while putting his trust in Allah. Then, if they are guided, all is well and good; otherwise, he should not grieve or feel sad, for that weakens one's resolve and saps one’s strength, and there is no benefit in it. Rather, he should carry on and persist in doing what he is required to do and aimed for, as anything other than that is beyond his means. Al-Saadi: 470.
Question: This verse contains a valuable lesson for a preacher to Allah. Explain.

(We have made all that is on earth as an adornment for it), what is fit for adornment such as clothing, foods, trees, and rivers, etc. (So that We may test them as to which of them is best in deeds) to test them as to which of them will be less inclined toward the adornment of this world. Ibn Juzay: 1/502.
Question: Allah made all kinds of adornment to this life for a great wisdom. What is it?

This verse re-directs the attention of those who are preoccupied with wonderous stories to being admonished and drawing lessons from their causes and consequences. That is why Allah begins by mentioning the state in which they were, (when the youths took refuge in the Cave, and said, "Our Lord, grant us mercy from Yourself, and show us the right way in our ordeal"). Ibn Ashur: 15/259.
Question: Attention should be directed to the admonishments and lessons from the stories rather than their wonders. How can you infer that from the presentation of the story of the people of the Cave?

This verse provides a clear proof of allowing fleeing for the sake of religion and leaving family, sons, relatives, friends, homes, and wealth behind for fear of persecution and adversity. The Prophet (ﷺ) migrated for the sake of religion, and so did his Companions. They left their homes, land, families, sons, relatives, and brothers in order to be safe with their religion from the persecution of the disbelievers. Al-Qurtubi: 13/216.
Question: Should the believer leave his homeland when he fears for his religion? Or should he stays and risks his religion?

Allah states that they were boys, young men; they were more accepting of the truth and more inclined to guidance than the elders, who had become stubbornly set in their ways and clung to the religion of falsehood. For the same reason, most of those who responded to Allah and His Messenger (ﷺ) were young people. As for the elders of Quraish, most of them remained on their religion and only a few of them became Muslims. Ibn Kathir: 3/72.
Question: People who are likely to accept the truth belong usually to which age group?

Meaning: We strengthened their hearts with patience, kept them firm, and secured them with the light of faith, so they became determined to migrate from the land of their people, leave their lavish and plentiful life behind, and head toward the Cave for the sake of their religion. Al-Baghawi: 3/17.
Question: How did Allah strengthen the hearts of the people of the Cave?

Strengthening the heart is the opposite of forsaking. Forsaking means removing the heart from the path of success, causing one to become heedless of Allah's remembrance, and follow his desire, which leads to the loss of his affairs. Strengthening the heart is binding it with the means of success, so the believer remembers Allah, and follows what pleases Him, so his affairs become sound. Ibn Al-Qayim: 2/157.
Question: In light of this pause, explain the difference between strengthening the heart and forsaking it.