Final answer:
Macbeth's sleeplessness and hallucinations reflect his overwhelming guilt and growing insanity after committing regicide, highlighting the play's themes of ambition and moral decline.
Step-by-step explanation:
The fact that Macbeth cannot sleep and hears voices praying indicates his deep sense of guilt and mental turmoil after murdering King Duncan. Sleep, often associated with innocence and peace, becomes unattainable for Macbeth, signifying the heavy burden of his conscience.
The voices he hears, symbolizing the goodness he has disrupted, further illustrate his internal conflict and descent into madness.
His inability to echo 'Amen' to the prayers signifies his alienation from God and good, recognizing himself as unworthy of divine grace because of his deeds. This psychological distress foregrounds the theme of the consequences of unchecked ambition and moral corrosion in Shakespeare's tragedy.