Followers of Islam are called Muslims. Muslims are monotheists and worship an omniscient God known in Arabic as Allah. The followers of Islam strive to live in complete submission to Allah. They believe that everything happens according to Allah’s will, but humans have free will.

Following are the two categories:

1. Muslims by Birth or Origin: A child whose both parents are Muslim is a Muslim and even if one of the parents is a Muslim the child will be Muslim.
2. By Religion or Conversion: A convert is a person who renounces his faith and adopts another religion but the conversion should be bonafide and not with any ulterior motive or intention. 

In the case of Sarla Mudgal v. Union of India (1995 AIR 1531) The husband was already married under Hindu law and he embraced Islam and solemnized a second marriage under Muslim Law. The court held that the second marriage of a Hindu husband after conversion to Islam without having his first marriage dissolved under Hindu law would be invalid.

In Lily Thomas v. Union of India (AIR 2000 SC 1650) the Supreme court held that one personal law cannot be used to defeat the spirit or purpose of another personal law. The Supreme Court held that the husband is guilty of the offence of bigamy under section 494 of IPC.

In Azima Bibi v. Munshi Samalanand, (1912) 17 CWN 121, it was observed that a child born out of a Muslim couple would be Muslim, even if he by choice goes to a Hindu temple. The person would be a Muslim, till the time he does not renounce his religion and converts to another religion.

In Bhaiya Sher Babadur v. Bhaiya Ganga Baksh Singh, (1914) 41 IA 1, it was held that

if a Muslim woman has a child from a Hindu man but the child from the time he was born was brought up as a Hindu, then, in this case, he would be called

Under Muslim law, if a married man renounces his religion then in that case his marriage ends immediately but this is not the case for Muslim women who convert, her marriage would not come to an end if her marriage was done according to the rituals of Muslim law. Unless and until she was a convert Muslim and again re-embraces her faith.

These two points are the minimum and fundamental rules for a person to be called a Muslim

1. Muslim by Birth –                                               2.  Muslim by Conversion –

a. Believes in one God and                                       a.  Converts by profession of Islam.

b. Prophet-hood of Muhammad                                b.  Converts by formal ceremony.

The Five Commandments of Islam are the basis of the Islamic faith. They are the core beliefs and practices that Muslims must follow

1. Shahada (Profession of Faith) :- It is the most fundamental expression of Islamic beliefs. It simply “There is no god but God, and Muhammad is the Messenger of God”
2. Salah/ Namaj (Prayer) :- Prayer rituals are required of each Muslim, and they take place five times a day, every day of the year. Prayer includes a reading from the beginning of the Quran, the sura, followed by prayer and reflection.
3. Zakat (Almsgiving):- The practice of charity is important in the Islamic faith, as Zakat . During their lives, Muslims are expected to give a fixed portion of their wealth to those less fortunate than themselves. Popular recipients of donations include the homeless, refugees of conflict, and people affected by natural disasters. The money provides housing, food, and clothing in most organizations.
4. Sawm / Roza (Fasting):- Fasting in the month of Ramadan is mandatory for every adult Muslim, in which Muslims fast from dawn to dusk.
5. Hajj (Pilgrimage):- All Muslims who are able are required to make the Pilgrimage to Mecca and the surrounding holy sites at least once in their lives

Although the Five Pillars have remained the same since the founding of the faith by the Prophet Muhammad in the seventh century, they have been slightly adapted to fit the needs of the present. For example, the Hajj used to be required every year, but now in many cases a person only needs it once in a lifetime.Muslims who wish to live a life like Muhammad are expected to complete the Five Pillars and participate in rituals of the faith as far as possible.