How does the author use foreshadowing in Doubt?

Scene Five is the climax of the play to this point, with many of its previously discussed narrative threads playing out in a confrontation notable for its economy of writing, its emotional intensity, and its metaphorical resonance. Sister Aloysius' narrow mindedness, her determination, her suspicions, her attitudes towards men, and her genuine fear for the well being of Donald Muller all play key roles in defining her attacks on Father Flynn. It's important to note that there is also an indication here of her capacity for falsehood. In her obvious lie about Sister Veronica's sight, there's clear foreshadowing of her lie about the phone call she made to Father Flynn's previous parish later in the play.