Answer:
DIVEST
Context Clues: She had bread for the hungry, clothes for the naked, and comfort for every mourner that came within her reach. Slavery soon proved its ability to divest her of these heavenly qualities. Under its influence, the tender heart became stone, and the lamblike disposition gave way to one of tiger-like fierceness.
The third sentence indicates that slavery has the capability to change people and make them cruel and fierce. This provides a clue to the meaning of the word divest, which we can infer as taking off something from someone.
Guessed Definition: take off something from someone.
Dictionary Definition: to take away, deprive, or strip (someone or something), esp. of property or rights.
APT
Context Clues: She was an apt woman; and a little experience soon demonstrated, to her satisfaction, that education and slavery were incompatible with each other.
The part where the author talks about the demonstrated experience and education reveals to us that this woman had some valuable experience, which made her apt (capable) to do many things.
Guessed Definition: capable
Dictionary Definition: being quick to learn; bright.
BESTOW
Context clues: This bread I used to bestow upon the hungry little urchins, who, in return, would give me that more valuable bread of knowledge.
The hungry little urchins offered to him knowledge in return, as he provide them with bread, because they were hungry. Therefore, we could conclude that bestow means give or provide with something.
Guessed Definition: give
Dictionary Definition: present as a gift; give; confer:
CONSOLE
Context clues: These words used to trouble them; they would express for me the liveliest sympathy, and console me with the hope that something would occur by which I might be free.
This person suffers a lot because of his freedom, so he needs sympathy and hope that one day he could be free. Therefore, console could mean provide comfort with the fact that someday he could be free.
Guessed Definition: comfort
Dictionary Definition: to lessen the grief, sorrow, or disappointment of;
give comfort to.