He was astonished at the efforts of Therese to prevent the impotent old woman committing suicide.

Now that the presence of the old lady had become useless to them he desired her death.

He would not have killed her, but as she wished to die, he did not see the use of depriving her of the means to do so.
"But, let her be!" he shouted to his wife.

"It will be a good riddance.
We shall, perhaps, be happier when she is no longer here." This remark repeated several times in the hearing of Madame Raquin, caused her extraordinary emotion.

She feared that the hope expressed by Laurent might be realised, and that after her death the couple would enjoy calm and happiness.