The antonyms for "disbelieved" can be viewed in a positive light compared to the negative connotation that disbelief possesses. A few antonyms of the word disbelieve are belief, trust, confidence, faith, and rely, among others.
When someone believes, they have faith or confidence in something or someone. Trust, on the other hand, is one's assurance in the integrity, reliability, or capability of someone. Relying on something, a person or an organization means putting our trust in them to perform a specific task dependably.
In short, belief and trust are the exact opposite of disbelief. In daily life, we need to cultivate trust and faith to deal with various situations, and these qualities help us maintain healthy relationships with others.