The man was cunningly able to dissemble his feelings on the matter, which saved his family much worry.
In “The Devil and Tom Walker” Irving is saying that the values in American society lie in the wrong place chosing wealth and financial prosperity over the well-being of others.
Irving sees America becoming greedy and warns the reader not to follow Tom Walkers ´s path that led him to exchange his soul to the devil blinded by his ambition for money.
This statement reflects the popular themes of individualism in the romantic era. The American romantics believed that a man's choices decided his fate. Washington Irving shows how Tom chooses the wrong direction that led him astray from the true values of humanity.
The answer is
Yet.
A coordinated conjuction is a word that joins or coordinates two senteces together, in this case the word yet is conectint he was but a child, and giving meaning to the whole sentece by conecting to he did so much for others, if you read it without the yet, the sentence looses force in the statement.