Quran

In combining these two opposite qualities -firmness and mercy-, Allah alludes to the originality of judgment and the wisdom in their reasoning. They maintain their attitudes and conduct their deeds maturely and wisely so that not a single quality dominates them at all times, nor will they rush to act inherently or without vision. Ibn Ashur: 26/205.
Question: What is the benefit of combining the believers' descriptions, firmness and mercy?

(Firm against the disbelievers), they are serious and strive hard in opposing them, putting their utmost effort into achieving that. (Merciful among themselves), loving one another, showing mercy and kindness to one another, like a single body; each of them loves for his brother what he loves for himself. This is how they treat one another. As for their interactions with their Creator, (You see them bowing and prostrating [in prayer]). Al-Saadi: 795.
Question: After mentioning the believers' firmness against the disbelievers and their mercy toward the believers, Allah mentions their prayers. Why ?

If Allah, the Almighty, forbids them from raising their voices over the Messenger's (ﷺ) voice, so how would it be for raising their opinions over his teachings that he brought from Allah?! Ibn Al-Qayim: 3/5.
Question: This verse indicates that sound reason should follow the true revelation. Explain.

This is an emphatic prohibition on giving precedence to any view over that of the Messenger (ﷺ) for once the Sunnah of Allah's Messenger (ﷺ) is clear, it becomes obligatory to follow and give precedence to it over everything else, no matter what it is. Al-Saadi: 799.
Question: What is the Sharia ruling on following other than the clear sayings of the Messenger (ﷺ)?

Some scholars disliked raising voices when visiting the Prophet's (ﷺ) gravesite. Moreover, some scholars disliked raising voices while sitting with scholars in study circles; this is to honor them, as they are the inheritors of the Prophets. Al-Qurtubi: 19/361.
Question: What is the practical implementation of this verse?

The obvious meaning of this verse is that one's deeds may become worthless without him realizing it. Al-Shanqiti: 7/403.
Question: Do you understand from this verse that one's deeds may become worthless without him realizing it?

Allah criticized them for their lack of understanding, because they did not understand His command to observe etiquette with His Messenger (ﷺ) and show him respect, for it is a sign of intellect to be polite and observe etiquette. A person's manners are a sign of intellect, and indicate that Allah intends good for him. Al-Saadi: 799.
Question: What is the link between intellect and politeness in light of this verse?