In order to answer this question, it is necessary that we briefly recount the story of Prophet Lot from both the Quran and Bible's perspective:

The story of Lot in the Quran

This story has been recounted several times in different chapters of the Holy Quran and words on it can also be found in Islamic traditions. Here, relying on verses of surah Hijr and other surahs, this story will be mentioned:

"So when the messengers came to Lot's family, he said," You are indeed strangers [to me]. They said," Rather we bring you what they used to doubt. We bring you the truth, and indeed we speak truly. Take your family in a watch of the night; and follow in their rear, and none of you should turn round, and proceed as you are bidden." We apprised him of the matter that these will be rooted out by dawn. The people of the city came, rejoicing. He said," These are indeed my guests. Do not bring dishonour on me. Be wary of Allah and do not humiliate me." They said," Did we not forbid you for [defending] strangers?" He said," These are my daughters, [marry them] if you should do anything."[1] Certainly they even solicited of him his guests, whereat We blotted out their eyes, [saying] "Taste My punishment and My warnings!"[2] "So the Cry seized them at sunrise, and We made its topmost part its nethermost, and rained on them stones of shale!"[3] "So We delivered him and his family, except his wife; she was one of those who remained behind."[4]

The story of Lot in the Bible

"And there came two angels to Sodom at even…and they turned in unto him, and entered into his house…But before they lay down, the men of the city, even the men of Sodom, compassed the house round…and they called unto Lot, and said unto him, Where are the men which came in to thee this night? Bring them out unto us, that we may know them. Lot went out at the door unto them…and said, I pray you, brethren, do not so wickedly. Behold now, I have two daughters which have not known man; let me, I pray you, bring themout unto you, and do ye to them as is good in your eyes. Only unto these men do nothing; for therefore came they under the shadow of my roof…But the men [the two angels] put forth their hand, and pulled Lot into the house to them, and shut to the door. And they smote the men that were at the door of the house with blindness...whatsoever thou hast in the city, bring them out of this place, for we will destroy this place, because the cry of them is waxen great before the face of the LORD; and the LORD hath sent us to destroy it…Then the LORD rained upon Sodom and upon Gomorrah brimstone and fire from the LORD out of heaven…and he overthrew those citiesand all the plain, and all the inhabitants of the cities, and that which grew upon the ground. But his wife looked back from behind him, and she became a pillar of salt. And Lot went up out of Zo'ar…he dwelt in a cave, he and his two daughters…And the firstborn said unto the younger…come, let us make our father drink wine, and we will lie with him, that we may preserve seed of our father.And they made their father drink wine that night: and the firstborn went in, and lay with her father; and he perceived not when she lay down, nor when she arose…And they made their father drink wine that night also: and the younger arose, and lay with him; and he perceived not when she lay down, nor when she arose…Thus were both the daughters of Lot with child by their father".[5]

These were brief accounts of the story of Lot in the Quran and Bible. They have many similarities, it can even be said that they share the same general points and fundamentals, other than the incest of his daughters with their father; the Quran not only makes no mention of this, but according to Islamic teachings, this part of the story is an addition made later and an alteration in the original Torah and is in contradiction with the infallibility of the prophets. We also know his daughters to be pure and chaste who were saved from the punishment of their people. Therefore, such an act by them is totally refuted. Much of what is found in the Bible today is not accepted by the Muslims.

On the other hand, what has been mentioned in the Quran is completely accepted and is also in compliance with human and religious principles.

It seems that the only point remaining vague in the story of Lot in the Quran that has also been mentioned in the Bible is the matter of him saying: "O my people! Here are my daughters…"; the question is how can a prophet of God 'offer' his daughters to the disbelievers and misguided?! Relying on the generic rules and principles that can be derived from the Quran, commentators have asserted under the verse "قَالَ یَا قَوْمِ هَؤُلَاءِ بَنَاتىِ هُنَّ أَطْهَرُ لَکُم"[6] that the sentence "هؤُلاءِ بَناتِی" has been added the clause "هُنَّ أَطْهَرُ لَکُمْ" (they are purer for you) to show that what Lot meant by 'offering' his daughters was that he was asking the people to marry them, not to commit the ugly act of fornication with them and satisfy their illegitimate desires through such; it is impossible for one with the status of prophethood to ever make such a suggestion. There is no purity and chastity in fornication, as the Quran says: "And do not approach fornication. It is indeed an indecency and an evil way"[7]. The prohibition of fornication is a law that God has enacted in all divine religions. It had also been enacted during Lot's time. So, the clause "هُنَّ أَطْهَرُ لَکُمْ" is the greatest evidence that what Lot was intending was marriage, not fornication.[8]

Also, the goal of Prophet Lot in suggesting the sinners to marry his daughters, while his daughters were a small number compared to the sinners, was to leave them no excuse and show to what extremes he was willing to go to, to save the face of his guests and save his people of the swamp of corruption[9]. Clearly, suggesting marriage with such an intention not only isn't wrong, but is also applauded.