Thousand Lights Mosque (ஆயிரம் விளக்கு மசூதி), a multi-domed mosque in Anna Salai in Chennai, Tamil Nadu, India, is one of the largest mosques in the country and is a revered place of worship for Muslims. It was built by Nawab Umdat-ul-Umrah in 1810. Thousand Lights Mosque is a common mosque for all Muslims. It is also a primary holy place for Shias. The 10th of Moharram is the most important day where Shias mourn for Imam Hussain and participate in Matam in mosques. Thousand Lights Mosque is home of Chief Shia Ghazi Moulana Ghulam Mahadi Khan of Tamil Nadu and a Shia burial ground is inside.
The Shias who live in the Thousand Lights neighborhood and Royapettah are the followers of the Ahl al-Bayt ("the People of the House"). Individuals among his descendants, who are known as infallible Imāms, have special spiritual and political authority over the community and they acquired this authority since God gave it to them just the same way God chose Adam, Noah, Abraham, Moses, David, Jesus and other prophets, Imams such as the offspring of Abraham and from amongst the children of Israel as well as kings, such as King Saul. Shia Muslims further believe that Ali, Muhammad's cousin and son-in-law, was the first of the Twelve Imams and was the rightful successor to Muhammad and thus reject the legitimacy of the first three caliphs.
The grandsons of the Prophet Muhammad, Hasan ibn Ali and Husayn Ibn Ali are agreed upon by all Muslims to be the "leaders of all youths in Paradise." Shias also believe that these sons of Imam Ali were the true leaders and caliphs of the Muslims. Shias regard Ali as the second most important figure after Prophet Muhammad. Muhammad suggested on various occasions during his lifetime that Ali should be the leader of Muslims after his demise. According to this view, Ali as the successor of Muhammad not only ruled over the community in justice, but also interpreted the Shariah Law and its esoteric meaning. Hence he was regarded as being free from error and sin (infallible), and appointed by God by divine decree (Nass) to be the first Imam.
Ali is known as "perfect man" (al-insan al-kamil) similar to Muhammad according to Shia viewpoint. As a result, Shias favor Hadiths attributed to Muhammad and Imāms, and credited to the Prophet's family and close associates, in contrast to the Sunni traditions where the Sunnah is largely narrated by the Prophet Muhammad's companions, whom Sunnis hold to all be trustworthy. Thus the Qurʻān and Hadith interpretation and differences in Hadith narrators are the main distinction of the Shias.