In Bengali Language, a man cannot be a ‘Dharmanirapeksha’ or secular man and a state cannot be a ‘Dharmanirapeksha Rastra’ or secular state, because it (Dharma) is the true essence of humanity. In Bangladesh, terminologically, there has a debate in Bengali dharmanirapekshta and English word of secularism. It can be said that the 5th and 8th amendment bills of Bangladesh constitution were anti-secular, but the 15th amendment bill is both secular and anti-secular. This amendment creates an obscure meaning of the term ‘Secularism’ which also promotes and strengthens the ideological debate on religion and secularism in Bangladesh. This book, therefore, tries to give answer the following questions and to provide a prolouge for ‘Bangladesh Constitution’. 1. Is there any distinct arena for Religion and Politics in a society? 2. ‘Renders unto Ceaser the things that are Ceasers and unto God the things that are Gods’ and ‘Religion is only belonging to individual, not belonging to collective or a state’- Are these two notions same? 3. Is Secularism and Dharmanirapekshata a same Concept?