I don't know of any religious doctrine, but for me as a Christian, I don't see trading as a crime. It depends on your approach and what you're trading. Their are things considered as illegal when it comes to trading digital assets, like, trade washing. Which means, using different accounts to buy and sell digital currencies for yourself, like, buying and selling back to yourself to make good profit. Using different payment methods that isn't your own is considered red flagged if you're a P2P trader as a digital asset vendor. Some users consider 'digital asset lending as illegal, staking is similar to digital asset lending, because it requires you given out portion of your digital assets to other users for funding purposes.
But for me, it isn't illegal here in my country and also religious wise, because you're doing it clean, and you aren't cheating the system, no fraudulent charges found by you. That's why we need a trustee exchange to our trading on, most exchanges are created by scammers, when you deposit your hard earned digital assets to their platform and use it for Investments like this, you lose it all, because what you're trading isn't genuine, it is run by scammers.