It took a brave man to stand up to four car loads of men bent on a lynching, but that's what Atticus did that night at the jail. Although he must have expected Sheriff Tate to eventually appear, he soon found out from the men that the sheriff had been sent on "a snipe hunt." Atticus realized then that he was on his own, but even then, he seemed to be in control of the situation. Atticus told the men that Tom was asleep and not to wake him, so the mob obeyed, speaking in whispers until the arrival of the children. It took the appearance of Jem, Scout and Dill to calm the men, who probably would not have allowed Atticus to talk them out of their murderous intentions.
Dill announced that they were all heroes the next morning.
"It's all over town... how we held off a hundred folks with our bare hands."
But perhaps the best quotation of the courage displayed came from the always humble Atticus himself.
Jem spoke. "(Mr. Cunningham would have) killed you last night when he first went there."
"He might have hurt me a little," Atticus conceded, "but, son, you'll understand folks a little better when you're older. A mob's always made up of people, no matter what... Every mob in every little Southern town is always made up of people you know--doesn't say much for them, does it?"
When the Old Sarum bunch appears at the jailhouse demanding that Atticus turn Tom Robinson over to them, he bravely challenges these men: "Do you really think so?"
It certainly displays courage on the part of Atticus that he asks his daring question right after being told that Sheriff Tate and his men are "deep in the woods [and] they won't get out till mornin'." Atticus then understands that he is alone before all those angry men who have emptied out of dusty cars in ones and twos and who smell of stale whisky. If they advance upon him, Atticus now believes that he has no one to support him.
Fortunately for Atticus, the intrusion of the children changes things. Scout's innocent question about his "entailment" reminds Mr. Cunningham of the way Atticus has so graciously done what he can for him and has accepted vegetables as payment regarding this "entailment." Uncomfortable now with his previous intentions, Mr. Cunningham orders the others to depart with him, and the men return to the cars and drive off.