Step-by-step explanation:
Lady Macbeth is afraid that her husband is too kind and caring to kill King Duncan. She says in her soliloquy of Act I scene V-
yet do I fear thy nature;
It is too full o' the milk of human kindness
To catch the nearest way:
She says that he is certainly ambitious, but does not have enough evil in him to kill in cold blood-
thou wouldst be great;
Art not without ambition, but without
The illness should attend it: