What is the next great event that the prophets have told us will happen?

The entire creation is waiting for the manifestation, the unveiling, of the sons of God.

Romans 8:19  For the earnest expectation of the creature waiteth for the manifestation of the sons of God.

The word, manifestation, is a translation of the Greek word, apocalypse.  The Greek word, apocalypse, means, "the removal of a veil."  The only Biblical reference that explains this metaphore is a reference to Jesus that explains that the veil is the flesh.

Hebrews 10:20
By a new and living way, which he hath consecrated for us, through the veil, that is to say, his flesh;

This manifestation or unveiling is mentioned throughout Scripture.  It is the same as the apocalypse, which is also the unveiling.

Jesus paid for all of this on the cross.  It's a shame that so many Christians miss out.  Some won't even be filled with the Spirit or receive the gifts of the Spirit.  Some won't walk on with God even after Jesus fully paid for all of this.  It's a free gift to all who will receive it.  Whoever will may come.