Answer:
In the passage, when Phillis Wheatley uses the word "forsook" to describe the sun, she is expressing the idea that the sun has departed or left the eastern horizon. In other words, the sun has disappeared from the eastern part of the sky as it sets, signifying the end of the day and the transition to evening or night. The word "forsook" implies a sense of departure or abandonment in the context of the sun's movement across the sky.