Quran

Abu Huraira (t) said: "When Allah says, (a great reward), then who can measure that?" Al-Qurtubi: 6/324.
Question: Allah says: (a great reward), what does that indicate?

He will multiply it tenfold or more, according to the nature of the deed and how beneficial it was, and according to the situation of the doer in terms of sincerity, love and righteousness. Al-Saadi: 179.
Question: What makes the multiplication of rewards for good deeds vary?

The Prophet (r)said to Ibn Masoud: "Recite the Quran to me." He said: How will I recite it to you when it was revealed to you?" He said, "I love to hear it recited by others." So, I recited Surat-An-Nisa' to him until I reached this verse: (How will it be when We bring a witness from every nation, and bring you (O Prophet) as a witness against these (people)). The Prophet (r) said: "That is enough." I looked at him and saw his eyes overflowing with tears. Ibn Taimyah: 2/249.
Question: Why did the Prophet's (r) eyes overflow with tears when he heard this verse?

This indicates that the person praying should guard against what distracts him and occupies his heart, and that he should purify himself from what defiles it, because if purifying the body is obligatory, then purifying the heart is more important. If the place of prayer is protected from someone who has become impure, then it is clearly a priority to protect the heart from impure thoughts. Al-Alusi: 5/401.
Question: What does the prohibition of approaching prayer while drunk symbolize?

We may also understand from the meaning of the verse that it is not allowed to start praying when one is extremely drowsy, to the point that he is not aware of what he is saying and doing. Indeed, it may indicate that the one who wants to pray should deal with anything that is distracting him, such as resisting the urge to use the toilet, craving for food and the like. Al-Saadi: 179.
Question: The verse indicates that whoever wants to pray must clear his mind. Explain.

I believe that the wisdom of its enactment is to establish the necessity of purity in the hearts of believers, and to establish the sanctity of prayer, and to elevate its importance in their hearts, leaving them no situation in which they consider themselves to be praying without. This emphasizes the importance of communing with Allah. Ibn Ashur: 5/69.
Question: What is the wisdom behind the legislation of Tayammum for purity?

His saying: (Allah is Ever-Pardoning, All-Forgiving) is a conclusion to the ruling of the concession, as He pardoned the Muslims and did not require them to wash or perform ablution when sick, nor did He wait for the availability of water when it was not available, so that the prayers would become numerous and it would be difficult for them to make up for them. Ibn Ashur: 5/71.
Question: This verse concludes with (Allah is Ever-Pardoning, All-Forgiving). Why?