Quran

This is one of the greatest blessings that Allah may bestow upon His servant, by making him a leader by means of whom people are guided and whom many people follow. Al-Saadi: 527.
Question: Allah made Abraham (u) and his descendants leaders of guidance. What is a useful lesson in that? What blessing does a person who memorizes the Quran and the student of Islamic knowledge feel when they read this verse?

(This includes all good deeds with respect to duties toward Allah and people. (Establish prayer and give zakah), this comes under the category of mentioning specific deeds after speaking in general terms due to the noble status and virtue of these two acts of worship. Whoever performs them properly, his religious commitment will be sound, but whoever neglects them will be more neglectful of other matters. Moreover, prayer is the best of the deeds that are due to Allah, and zakah is the best of the deeds that involve kindness toward His creation. Al-Saadi: 527.
Question: Allah singles the prayer and zakah for mention, even though they are included in righteous deeds. Why?

(And We gave understanding of it to Solomon), We helped him to understand this case and reach the right verdict. This does not mean that Allah did not enable David to reach the right verdict in other cases. Hence, He pointed this out, as He says: (And to each of them), namely David and Solomon (We gave judgement and knowledge). This indicates that a judge may reach the right conclusion or he may get it wrong; he is not to be blamed if he makes a mistake so long as he did his best. Al-Saadi: 528.
Question: When is a ruler, a judge, a teacher, or a parent not blamed for a mistake?

Alhasan said: "If it was not for this verse, you would have seen all judges doomed, but Allah praised Solomon for being correct, and excused David for doing his best." Al-Qurtubi: 14/237.
Question: Describe Allah's mercy toward scholars and judges in light of this verse.

That is because he was one of the most devoted of worshipers and one of those who remembered Allah the most, glorifying and praising Him. Al-Saadi: 528.
Question: Allah subjected the mountains and birds, along with David, to exalt Him. Why?

It is apparent that saying, (And We were doing that) is a confirmation of this verse: (And We subjected the mountains to exalt [Us], along with David and [also] the birds). The reason for this confirmation is that subjecting the mountains and their exaltation of Allah is a supernatural event, which is prone to denial by ignorant disbelievers. Al-Shanqiti: 4/232.
Question: The verse ends with: (And We were doing that), why?

The servant's gratitude toward his Lord: Using His blessings to obey Him.
The Lord’s appreciation toward his servant: Giving him a great reward for his small deed. Al-Shanqiti: 4/234.
Question: When is a servant described as (grateful)? How does Allah appreciate his servant?