If so - what do you think enables this attitude?
What is it about a culture's mentality that makes the people in that culture comfortable belonging to two different religions?
Possibly an underlying attitude of inclusivity rather than exclusivity?
I wonder if the general tenor of cultural relations also plays into this?
As a Christian I am inclusive of all religions in that I see the answer the desire to seek a common end, as a Christian I am exclusive in the fact that I believe my tradition is the most comprehensive and, for me, the most complete and comprehensible answer to the questions.
India I only know generally, where seemingly the Hindu religion has rubbed along quite happily incorporating 'alien gods' — but I think it's generally understood that those Gods are interpreted in a very Hindu context — so you may see a statue of Christ on a Hindu altar, but the understanding of Christ is within a Hindu rather than Christian or even multi-faith context.
Japan's history I am more conversant with. Shinto and Buddhism got along quite happily, with shrines and temples changing hands etc.
But there has always been conflict. In Japan, the history of militant Buddhist monasteries are legendary, and the history of swordsmanship is closely linked to Shinto roots.
Today it seems the fluid shoulders are hardening. There's been disputes between Moslems and Hindus in India since the partition of India in '48 (a bloodbath), and more recent cases of Hindu and Buddhist conflicts. Politics, so cultural attitudes, play into this.
The
niqab "face veil", and all styles of veiling worn by some Muslim women is seen as founded in Moslem hijab ("modesty"). Such veiling actually pre-dates Islam and was in use by some pre-Islamic Arabic communities. The particular styles are usually associated with a particular region — so we can see that the veil is actually a cultural practice incorporated into Islam, rather than determined by it.
In your own case for example, I wonder whether the celebration of festivals says more about Nepalese cultural heritage/homesickness than particular religious beliefs?
A good question, and the East is a big place!
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In my own heritage, early Irish Christianity ('Celtic Christianity' so called, although the term is somewhat ill-applied), simply incorporated pre-Christian Irish mythology into the Christian canon, so there are stories of Brigid, an ancient Irish goddess of sorts, being present as midwife at the birth of Christ!