What is the meaning and scope of fitrah in Islamic sources and classical literature?

 فَأَقِمْ وَجْهَكَ لِلدِّينِ حَنِيفًا ۚ فِطْرَتَ ٱللَّهِ ٱلَّتِى فَطَرَ ٱلنَّاسَ عَلَيْهَا ۚ لَا تَبْدِيلَ لِخَلْقِ ٱللَّهِ ۚ ذَٰلِكَ ٱلدِّينُ ٱلْقَيِّمُ وَلَٰكِنَّ أَكْثَرَ ٱلنَّاسِ لَا يَعْلَمُونَ

So direct your face toward the religion, inclining to truth. [Adhere to] the fitrah of Allah upon which He has created [all] people. No change should there be in the creation of Allah. That is the correct religion, but most of the people do not know. [Surah Ar Rum (The Romans) - 30]

Fitrah is the spiritual reality that reflects the original and pure state of humans as created by Allah. Humans have a natural tendency to believe in a higher power or a creator, and this tendency may be influenced by cognitive, social, and cultural factors. Fitrah is related to the innate moral sense or conscience that humans have, which helps them distinguish between right and wrong. 

It is related to another verse in Surah Al-A’raf (The Heights), verse 172, which states that Allah took a covenant from all the souls before their creation, testifying that He is their Lord. This is also considered as part of the fitrah, as every human has a natural recognition of Allah’s lordship in their conscience.

وَإِذْ أَخَذَ رَبُّكَ مِنۢ بَنِىٓ ءَادَمَ مِن ظُهُورِهِمْ ذُرِّيَّتَهُمْ وَأَشْهَدَهُمْ عَلَىٰٓ أَنفُسِهِمْ أَلَسْتُ بِرَبِّكُمْ ۖ قَالُوا۟ بَلَىٰ ۛ شَهِدْنَآ ۛ أَن تَقُولُوا۟ يَوْمَ ٱلْقِيَٰمَةِ إِنَّا كُنَّا عَنْ هَٰذَا غَٰفِلِينَ

And [mention] when your Lord took from the children of Adam - from their loins - their descendants and made them testify of themselves, [saying to them], "Am I not your Lord?" They said, "Yes, we have testified." [This] - lest you should say on the day of Resurrection, "Indeed, we were of this unaware."

Hadith reported by Muslim:

Abu Hurayrah said: “The Messenger of Allaah (peace and blessings of Allaah be upon him) said: ‘There is no child who is not born in a state of fitrah (natural inclination towards Islam), then his parents make him into a Jew or a Christian or a Magian, just as animals produce whole animals (i.e., undamaged). Do you find anything mutilated?’ Then he recited the aayah (interpretation of the meaning): ‘The Fitrah of Allaah upon which He has created mankind. No change let there be in Khalq‑illaah (i.e. the Religion of Allaah — Islamic Monotheism)’”

These verse and hadith affirm that Allah created humans with a natural inclination to worship Him alone and follow His guidance, but they may deviate from it due to external influences or temptations.

Fitrah is in harmony with the way of the prophets, who were sent by God to guide humans to the right path. Some examples are Noah, Abraham, Moses, Jesus, and their righteous companions, who all worshipped Allah alone and followed His laws. They also practiced some of the rituals and morals that are part of Islam, such as circumcision, prayer, fasting, charity, honesty, justice, and kindness. These prophets and their followers were also persecuted and oppressed by their people who deviated from the fitrah and followed false gods and idols. The final prophet Muhammad (peace and blessings be upon him) was sent to restore the original religion of Islam and to revive the fitrah in humanity. Thus, the concept of fitrah has a long and rich history in Islam, and it is the basis of the Islamic faith and practice. 

Fitrah contrasts with the Christian concept of original sin, which holds that all humans are born with a sinful nature due to the disobedience of Adam and Eve.