Here on earth it is true, yesterday is always before today; but there is a place where yesterday always follows today.

Why this works

This riddle plays with the concept of time and the order of words in a dictionary. While we think of "yesterday" occurring before "today" in our daily lives, in a dictionary, the words are arranged alphabetically. Thus, "yesterday" comes after "today" in this specific context, making the riddle clever and surprising by flipping our usual understanding of time and sequence!