Unfortunately, you have no legal right to demand that this money is returned to you. Tithing is a voluntary gift, and a gift once made is unconditionally made absent special circumstances. Deciding that you no longer feel positively about the recipient is not one of them. While you may certainly request the money back, your church has no obligation to return the money, and almost certainly won't.
This response is not offered as legal advice, but is only a general informational response for public interest. No one reading this is authorized to claim that an attorney client relationship exists with this writer or the writer's law firm.