yesterday was past and tomorrow is future and in between present is struggling for stability,philosopher explain events of great TIME by using words
whatever happened in past was good
whatever happening in present is good
and whatever going to happen in future is also good
so it mean every thing of past was good even those things and events which end with destruction like wars and present is also good even if everyday people dying in war of survival in human society.

what was good time or the events?Events was not good because they end with an end and what was time only a continuous process or the ultimate truth who never stop and its only explain by good