@Hardie that's impossible. I suggest you read the differences between hashing and encrypting. When you encrypt something, you encrypt it with a key so you can decrypt it.
However, when it comes to hashing, you can't do so. Hashing is only one way so we can never guess the original text from the hash.
Think about it, let say that someone hacked the bank website and managed to get all usernames and passwords. If he will be able to simply decrypt the hashing that means that there is no point storing the password hashed since it's already unsafe.. However in this case, they will simply have a long text that they can't guess what's the original text, hence keeping your password safe.