Can prophecies that have already been fulfilled be fulfilled again?

Some can. Whether a prophecy repeats is shown by its style. If it announces a single event, it is complete once fulfilled. If it is phrased as a lasting promise, it is fulfilled again and again.

Prophecies are not all built the same way. Some announce a particular event. Once it has happened, the prophecy is fulfilled and complete. Others are spoken in a form that expresses permanence. They describe how God will always act.

One example is the revelation to the Promised Messiah (as) that God will humiliate anyone who seeks to humiliate him. It does not speak of one single opponent but of everyone who takes that path. The same is true of the promise that God will help whoever helps him. Such words describe a lasting attitude of God. That is why they are fulfilled again and again, as long as there are people to whom they apply.

This can also be seen in the fact that some of these revelations were received again years later. The repetition shows that their content was not exhausted by the first event.

The Holy Qur’an knows this pattern. The first verse above says that God and His messengers will prevail. That held true for Noah (as), for Moses (as) and for the Holy Prophet Muhammad (saw), and it holds true today. So whoever reads a prophecy that has already been fulfilled should pay attention to its wording. The wording shows whether one may expect it to be fulfilled once more.