Bilef is a native English word of Angsa, which is derived from Old English. And un- is also the native prefix of Angsa English, so unbelief appeared very early, and Old English has the word ungeleafa. Helif was first seen in the mid-12C.
dis- is a Latin prefix, so disbelief is a cross of Latin and Ansa that was not used until the 1670s.
Beyond was closely associated with religion in the early days, so the meaning of unbelif is absence or lack of religious belief; disbelief of the truth of the gospel (no or lack of religious belief; Doubts about the truth of the gospel). As.
Example sentence 1] he claimed that all sin originated from unbelief and pride(He claimed that all sin stems from unbelief and pride.) Cambridge Dictionary of Senior Scholars].
By the 17th century, the religious overtones had been diluted, and the word disbelief meant "more active questioning". It is currently used in a secular context, such as:
Example sentence 2] his response was one of complete disbelief(His response was complete disbelief.) Cambridge Dictionary of Senior Scholars].
Example sentence 3】The reaction to the murders was one of shock and disbelief(The reaction to these cases has been shocking and incredulous.) [Longman Dictionary of Contemporary English].
The secular disbelief also has a prepositional phrase in disbelief, such as:
Example sentence 5] he stared at me in disbelief(He stared at me in disbelief.) [Oxford Dictionary of Senior Scholars].
Example sentence 6] rosie stared in disbelief(Rosie glares in disbelief.) [Longman Dictionary of Contemporary English].