If you're employee of MNC or any company that provides insurance in your remuneration package, then you'll find that your immediate family is automatically covered by the insurance. AFAIK you need to be legally married to allow your partner to enjoy that.

Beside that, tax filing can be done individually or with spouse. If your partner is not working or has less income, I guess you can combine to lower the tax brackets?

Note: I'm speaking entirely from own research, I'm not legally married.

Eh just for my own curiosity, please help me understand, which religion and why?