Answer
Wa Alaykum Assalam Dear Sister,
Thank you for your question and for contacting Ask About Islam.
Let us agree first that the state you are experiencing in terms of the level of your iman (faith) is a normal state. Muslim scholars agree that faith increases and decreases. It increases by drawing closer to God (Allah) and doing more acts of worship such as prayer, fasting, paying zakah, hajj, helping the poor and the needy, etc… It decreases by not doing these things.
We highly advise you not to give a chance to the whispers of Satan to occupy your mind and make you feel uncomfortable and lost.
We also appreciate your efforts to seek knowledge from authentic sources. Seeking knowledge is highly praised in Islam. We pray to Allah to help you in your pursuit of beneficial knowledge.
With regard to the issue of different interpretation of the Quran and the Sunnah, let us agree on basic principles.
Muslims believe that the Quran is the Final Word of God revealed to Prophet Muhammad (peace be upon him) via Angel Gabriel. The Quran is very comprehensive and it contains the guidelines of everything that we need to lead a happy life. The Quran does not contain the details of every single issue.
These details are to be found, Muslims believe, in the Sunnah of the Prophet, the second primary source of the Islamic Shari`ah. The Sunnah is not about the hadith transmitted from the Prophet only, but it is about his actions, characteristics, and his tacit approval.
The original state of Muslims is to remain a united nation. We read in the Quran what means:
{Hold fast to God’s rope all together; do not split into factions.} (Aal `Imran 3:103)
Therefore, we are commanded by Allah the Almighty not to split into fractions and be brothers to each other.
At the same time, Islam calls on Muslims to think, reflect and ponder. Muslim scholars are urged to exercise their personal reasoning to find solutions to problems that face Muslims. This is called in Islam Ijtihad whose details and rulings are to be found on the books of Usul al-Fiqh (Principles of Islamic Jurisprudence).
Not every scholar can practice ijtihad, he has to meet certain conditions and he has to be aware of the details of the issue being discussed.
This is the reason behind having different interpretations of some issues. But we have to keep in mind that the differences we find in Islam have to do with the details of the Shari`ah not the basics. The basics of Islam were, are, and will remain the same.
There is no difference among the scholars on the number of obligatory prayers, the amount of zakah to be paid by every Muslim, and the obligation to fast during the month of Ramadan and to perform Hajj once in a lifetime.
We read in the Quran what means:
{If your Lord had pleased, He would have made all people a single community, but they continue to have their differences.} (Hud 11:118)
This verse teaches us that being different is a divine bliss. Diversity is a natural phenomenon. We have to accept the others and their views as long as they do not contradict with the basic teachings of Islam. Difference of opinion is a mercy to all. The different opinions of scholars were to protect Muslims against ignorant people who would harm the Ummah by holding wrong interpretations of the rulings of the Shari`ah.
We have to understand that the different interpretations you are referring to have to do with very few verse and the scholars were unanimous on the majority of verses of the Quran. The disagreement came to the surface after the generation of the Companions and the followers. Sometimes these disagreements are in wording and they do not affect the meaning of the verses.
There is wisdom that some verse and hadiths are not quite clear so that people will do their best to grasp their intended meaning and there will be a space for discussions among scholars.
We have to understand also that if there is a different interpretation in the presence of a clear evidence from the Quran or the Sunnah, it has to be denounced. If there is a clear hadith but scholars differed on its authenticity, there is a space for personal reasoning to reach a decisive ruling on a certain issue.
The general rule with regard to matters of ijtihad is that this ijtihad is invalid if it goes against a verse from the Quran or a hadith from the Prophet (peace be upon him).
With regard to the issue of not touching the Quran by a menstruating woman, you as a Muslim have a belief in the divine command to do things and to avoid certain things. Your atheist friend does not have this concept. Therefore, whatever reasons you give her will not make her convinced.
So do not waste your time by occupying yourself with things beyond your capacity. Focus on having a strong relation with God in order to have a stronger faith. To your knowledge, there is an opinion that menstruating women can touch the Quran because there is no clear cut evidence that prevent her from doing so.
We pray to Allah to strengthen your faith and guide you to the best in this life and grant you Paradise in the Hereafter.
I hope this helps answer your questions.
Salam and please stay in touch.