Someone on a board I frequent asked this question.
I ask this question because I feel a bit of a interest in some Hindu deities. Vishnu, Shiva, Kali, etc.My reservations when it comes to add-mixing with Hinduism are that it's a really colonialist thing to do, appropriating bits and pieces of someone else's religion, chucking the original embedded meanings, and creating your own out of symbols that (to Hindus) probably didn't actually mean anything to you to begin with.
However, I'm under the impression that it is pretty explicit in Hinduism that there is no conversion. That your born into it, not invited in, etc. There is a purification type ceremonies for those that converted to Islam/Christianity as an effort to get back to come back to their born faith, but there is no conversion process.
However, does this prohibit the worship of deities? Is that considered innapropriate??
It's not merely that it's difficult to convert. It's also not merely a matter of "being a poser is bad, mmkay." It's a matter of having enough respect for a nation and a culture that has had its ownership of itself taken away by British colonialism, and is still working hard to get that power back. I would feel like I was shoving them backward in that struggle by appropriating their religion without paying extreme care to respect for the original cultural context.
A good example: There are a lot of Western Kali-worshippers who don't really actually care how Indians revere Kali. They may know one or two stories about her that sounded kinda cool, and she's sorta dark and scary which is how they feel sometimes, but Kali will be nice to them so it's not like they'll really have to deal with her wreaking havoc on their lives. Right? I mean, their Kali isn't at all like that scary indiscriminately-destroying goddess of violent transformation. Their Kali is theirs.
But this is disrespectful to the culture in which it came, the role that Kali plays within that culture, and if you believe that the gods are literally and actually real, it's disrespectful to Kali (since it entails uprooting her from her context, ignoring who she is, and telling her she needs to start being someone else).
It's possible to do this respectfully, and I have finally found some who do. But it's something to be very very careful about. Indians and Hindus have spent long enough in history being told that their culture, history, and traditions do not rightly belong to them. It's important for cultural outsiders not to participate in that by claiming what is theirs for ourselves.
More responses to this are at the thread here.