Did Allah grant Isaac and Jacob to Sarah because she was happy that the People of Lut would be destroyed? Why did then prophet Ibrahim not react same way but Allah SWT still didn't say anything bad about his reaction when they are two opposite reactions?
The reason for Sarah’s laughter is not given in the Quran. It is a mystery that scholars have tried to solve in various ways. The Persian Quran commentator al-Rāzī mentions eight different opinions on the reason for her laughter, and only one of them is that she was happy at the destruction of Lot’s people, I will discuss the opinions on her laughter below. The best interpretation in my opinion, as I will discuss below, is that her laughter was a laughter of joy and relief at finding out that the men were actually angels.
The Quran, in the following passage, suggests that they found out about the destruction of Lot’s people after being given the good news of having a son:
27. He set it before them. He said, “Will you not eat?”
28. And he harbored fear of them. They said, “Do not fear,” and they announced to him the good news of a knowledgeable boy.
29. His wife came forward crying out. She clasped her face, and said, “A barren old woman?”
30. They said, “Thus spoke your Lord. He is the Wise, the Knowing.”
31. He said, “What is your business, O envoys?”
32. They said, “We are sent to a people guilty of sin.” (The Quran, verses 51:27-32)
Another passage that retells the story is the following:
52. When they entered upon him, and said, “Peace.” He said, “We are wary of you.”
53. They said, “Do not fear; we bring you good news of a boy endowed with knowledge.”
54. He said, “Do you bring me good news, when old age has overtaken me? What good news do you bring?”
55. They said, “We bring you good news in truth, so do not despair.”
56. He said, “And who despairs of his Lord’s mercy but the lost?”
57. He said, “So what is your business, O envoys?”
58. They said, “We were sent to a sinful people.” (The Quran, verses 15:52-58)
Another passage compresses the story into the following two verses:
31. And when Our envoys brought Abraham the good news, they said, “We are going to destroy the people of this town; its people are wrongdoers.”
32. He said, “Yet Lot is in it.” They said, “We are well aware of who is in it. We will save him, and his family, except for his wife, who will remain behind.” (The Quran, verses 29:31-32)
In the following passage, which is the one you referred to, she is mentioned as laughing immediately after the people of Lot are mentioned:
70. But when he saw their hands not reaching towards it, he became suspicious of them, and conceived a fear of them. They said, “Do not fear, we were sent to the people of Lot.”
71. His wife was standing by, so she laughed. And We gave her good news of Isaac; and after Isaac, Jacob.
72. She said, “Alas for me. Shall I give birth, when I am an old woman, and this, my husband, is an old man? This is truly a strange thing.”
73. They said, “Do you marvel at the decree of God? The mercy and blessings of God are upon you, O people of the house. He is Praiseworthy and Glorious.”
74. When Abraham's fear subsided, and the good news had reached him, he started pleading with Us concerning the people of Lot. (The Quran, verses 11:70-74)
It appears that the Arab Quran commentator Ibn Kathir like the opinion that Sarah’s laughter was because of her happiness that the people of Lot would be destroyed. The Egyptian Arab scholar al-Suyuti in his very short commentary Tafsīr al-Jalālayn also summarily mentions this opinion without mentioning any of the others. But the reality is that the majority of scholars reject this view. The Persian scholar al-Wāḥidī mentions in his Quran commentary al-Basīṭ that Ibn ʿAbbās and Wahb ibn Munabbih had the opinion that her laughter was due to the strangeness of the news of having a son at her old age (this is also the reason for her laughter mentioned in the Torah in Genesis 18:11-14). Even though in verse 11:71 her laughter is mentioned before she is given the news of having a son, in Arabic literary writing something that is mentioned after another thing could have actually happened before it (known as al-taqdīm wa-l-taʾkhīr).
According to Muqatil (an early Persian scholar of tafsir), she may have been laughing or sneering at Abraham’s fear (peace be upon him) (because he was a tribal chief and it was out of place for him to act fearful of anyone), while according to the Persian scholar al-Farrāʾ (one of the great authorities on the Arabic language and on the interpretation of the Quran) her laughter was a laughter of relief. She had been afraid the angels were men planning to do violence to them, so when they said they were from God, she laughed with joy. The Persian Quran commentator Al-Ṭabarī mentions the various opinions on the matter but he himself sides with the opinion that she was laughing because she marveled at the way they people of Lot were going to be destroyed while they were unaware (she wasn’t happy at their destruction, she was being philosophical about it).
There also an entirely different line of interpretation, mentioned by most scholars, that interprets the word that is translated in English as “she laughed” to mean “she [started] menstruating”, because the word is used in Arabic poetry both to mean laughter and to mean menstruation depending on the context. This interpretation is rejected by scholars like al-Farrāʾ, but it is actually plausible because of the context. Sarah is a very old woman and probably has not menstruated in many years. But now she is about to be given the news that she will bear a son, and it is fitting if she starts menstruating at that time as a sign that her reproductive system is starting to function like a younger woman’s again.
Among all of these possibilities, the strongest one appears to be al-Farrāʾ’s, that Sarah was laughing with joy and relief at finding out that these men were angels. One line of argument that strengthens this interpretation, which I have not seen mentioned in any of the Quran commentaries I looked at, is that by merging all of the above passages together we can create the following chronology:
- The angles appear to Abraham and his wife looking like men
- The become fearful of them.
- The angels tell them not to fear and say that they have been “sent” to the people of Lot, but without actually explaining their purpose
- The angels give them the tidings about Isaac and Jacob
- When Abraham calms down, he asks the angels what their business is regarding Lot’s people
- The angels explain
- Abraham argues with them and tries to save Lot’s people.
Looking at the Quranic passages, the angels only explain what they are planning to do regarding Lot’s people only after giving them the tidings about Isaac. Before giving them the tidings they may have made a casual mention of Lot’s people (as in 11:70) without giving the details. This by itself does not prove much, but it adds a some extra support to interpretations (like al-Farrāʾ’s) that disassociate Sarah’s laughter from the destruction of Lot’s people.
In summary, there is no compelling evidence that Sarah’s laughter was at the destruction of Lot’s people. It is only one possibility among many, and the best interpretation (in my opinion) is that her laughter was a laughter of relief.