I come from an evangelical, Christian, conservative home. For a long time I retained the christian (I've never been too conservative) but I had a difficult time reconciling it with the poly. I've never told any of my family and very few of my Christian friends. I miss my faith and I'm still trying to work all of this out for myself. Kudos to you for feeling confident and secure in your decisions. For me, it may just be that Christianity and I had some issues before this anyway. I hope that someday i'll figure out what I believe.
I think that many people like to believe that their interpretation of the Bible is the best or the most correct. I do believe that all texts, whether divinely inspired or not, require every human being to interpret it. The Bible has been interpreted in many different ways over history and it is not unreasonable to believe that there many be things that will change in their interpretation.
In general, the christian world is not kind to the poly/queer/kink communities. For the reason, I tend to keep quiet about these subjects in those circles. When I encounter individuals who are more open minded, I will sometimes come out to them.