Fulfilled prophecy as confirmation of receipt
A prophecy can only be known to the world through the interpretation and work of a prophet. If we presume that true prophecy might be the result of a time travel experiment, then a 'work of prophecy' might be meant as a 'confirmation of receipt'.
If a book of prophecy could be used to prove that sending messages through time is possible then how would future scientists go about to make sure that this work really can be used as proof for the success of their experiments and therewith prove the correctness of their theories?
There might be many methods of traveling through time. Two of the methods that could be used for communication are complementary. The first is the traditional method of recording a message on a medium to let it vintage. Time will pass by and when the message gets read, it will be at a future moment in time in relation to the capturing of that information.
The second method is based on the communication model described before. It uses unknown, unconventional and unproven physics. Although the technology might allow for bi-directional communication, for confirmation a second channel is necessary.
Since a vision is only visible to a limited number of people, Its the work of prophecy that needs to confirm the receipt of visions. It's through the written predictions that a prophecy will be known to the world and gets preserved.
A prophet interprets his vision before recording it to some medium. This might be a painting, written text or maybe in a later century a voice recording or a film. Although it leaves room for some free interpretation, recordings will date the receipt of a vision.
If the response is written badly it might disappear, get lost in the centuries or prove nothing. For future scientists It is therefore important to help a prophet construct a proper response that bears enough importance that it gets conserved through the centuries.
Maybe the easiest way would be, to have the prophet literally quote the message, facilitating the hiding of secret information that can only be deciphered by the future scientists themselves.
Ideally the prophet's work should contain a great many predictions. Some could become reality almost immediatelly but preferably after the prophets death, avoiding any temptation to alter or withdraw his work under pressure of interest groups.
Fulfilled prophecy gives a prophet credibility; unfulfilled predictions help to preserve his work through the centuries.
When predictions start to become fulfilled, people will get more interest in the not yet fulfilled predictions.