[desikawa]

I am starting to study the Bible. I have a question. God gave Joseph the power to interpret dreams, right? But doesn't God say that prophecy is a sin? Joseph was a kind of medium....
It's all very confusing. Did God change the rules somewhere after the Old Testament (I know he is allowed to, of course)?
I don't need defensive answers. I am not criticising. I have recently refound God, and am trying to learn more through Bible study. I am just confused about some things, and hope someone can direct me toward the answers......