Hey. I'm new to this stuff. I was always interested in the mystical arts, but my family's background is Christian. I've always been taught magic is bad or it doesn't exist but I purchased some tarot cards and a crystal a while back and have been making some pretty accurate readings with them so I want to learn. I personally consider myself still Christian. Kind of. I've gotten to the point where I believe God exists but he doesn't really care anymore. If anyone could give me some insight to why people think magic is bad and some insight to the craft itself I would be extremely grateful.
You can worship the same God and practice magic at the same time. As for the other question, everyone has their own opinion about magic and why some think magic is 'bad', that is subjective. Some may think that because of what other people say, and what their religion says about the subject. Your religion is your choice, you are able to be a Christianand practice magic, in fact, many people do that.
Eventually people fear or rejected things they dont know. Unfortunatelly magic has been labeled as a bad thing for centures among some people or even religious groups since they tend to link magic to something evil. People go through generations with the same teachings that guide them to understand that magical power comes from something divine or cursed and if they do not see it as evidence of something divine, it will obviously be something wrong.
Regarding the insight on craft you can read some articles and pinned posts at this website. It will help you alot.