What are the reasons for Hamlet's hesitation to kill Claudius in Hamlet?
There are several reasons as to why Prince Hamlet hesitates to kill King Claudius throughout the play. Initially, Hamlet is unsure that Claudius is responsible for his father's assassination. He even questions his father's ghost and wonders if the spirit has been sent from the devil. Hamlet also attempts to confirm Claudius's participation in his father's murder by reenacting King Hamlet's murder on stage in order to analyze Claudius's reaction. Being that Hamlet is a Christian prince, he is also concerned about his own soul and fears that he will be damned for eternity if he unjustly assassinates his uncle.
When Hamlet has the perfect opportunity to murder Claudius in act 3, scene 3, he unsheathes his sword only to contemplate his decision further. Hamlet says,
"Now might I do it pat. Now he is a-praying. And now I’ll do ’t. And so he goes to heaven. And so am I revenged.—That would be scanned. A villain kills my father, and, for that, I, his sole son, do this same villain send To heaven. Oh, this is hire and salary, not revenge." (3.3.74-80)
Hamlet once again reveals his religious mindstate by mentioning that he would be doing Claudius a favor by murdering him while he is praying. Hamlet believes that Claudius will go to heaven if he kills Claudius while he is confessing his sins.
While one could speculate that Hamlet also does not want to be accused of attempting to usurp power or to have Claudius's supporters attempt to harm him for assassinating the king, Hamlet's inability to act is most likely a combination of his moral and religious beliefs. He struggles to decide whether enacting revenge will doom his own soul or save King Claudius from eternal damnation.
Hamlet hesitates to kill Claudius because he wants to be certain that Claudius is guilty.
Hamlet reenacts a murderous scene, searching for a visible sign of guilt from Claudius.
Hamlet cautiously searches for a definitive, visible sign of guilt. He wants to be absolutely certain of Claudius' guilt.
This is a tragic flaw for Hamlet. His insistence upon finding visible guilt from Claudius delays his action of killing Claudius, thus delaying the avenging of his father's death.
Hamlet's procrastination is well reasoned in that he desires to know the truth in reference to his father's murderer.
Nonetheless, Hamlet's procrastination allows Claudius time to suspect Hamlet's actions of avenging his father's death.
Claudius has Hamlet banished in a plot to have Hamlet killed.
Although Hamlet's hesitation to kill Claudius is an honorable quality, it is a tragic flaw that costs Hamlet his life, ultimately.
One part of an answer is in the first scene of the play during the changing of the guard: "For this relief much thanks; 't is bitter cold, / And I am sick at heart." In Act 3, scene 3, while it is not as cold indoors, it is late at night and Hamlet must be tired. Another is found in ROMEO AND JULIET: "God shield I should disturb devotion"(ROM4.1). Hamlet still has only the speech of the Ghost as evidence, it seems. Then there is the question of morality and other things.