He calculated all the possible inconveniences of an intrigue with Therese, and only decided to attempt the adventure, when he felt convinced that it could be attended by no evil consequences.
Therese would have every interest to conceal their intimacy, and he could get rid of her whenever he pleased.

Even admitting that Camille discovered everything, and got angry, he would knock him down, if he became spiteful.

From every point of view that matter appeared to Laurent easy and engaging.
Henceforth he enjoyed gentle quietude, waiting for the hour to strike.
He had made up his mind to act boldly at the first opportunity.

In the future he saw comfortable evenings, with all the Raquins contributing to his enjoyment: Therese giving him her love, Madame Raquin wheedling him like a mother, and Camille chatting with him so that he might not feel too dull, at night, in the shop.
The portrait was almost completed, but the opportunity he desired did not occur.

Therese, depressed and anxious, continued to remain in the room.