Here are some options:
* Blessing: This is the most straightforward opposite, as a blessing is a positive wish or prayer, while a malediction is a curse.
* Benevolence: This implies a general attitude of kindness and good will, the opposite of the negativity inherent in a malediction.
* Encomium: This is a formal expression of praise or admiration, directly contrasting with the ill-wishes of a malediction.
* Eulogy: A eulogy is a speech in praise of someone who has died, the complete opposite of a curse intended to harm.
The best opposite for "malediction" will depend on the specific context in which you are using the word.