The Joad family shows courage in the act of picking up and moving to California in hopes of finding a better life. They could have remained in the more familiar Oklahoma, but they took a chance and went looking for work, not a handout.
At one point in the story we see a restaurant owner help out the family be selling them a loaf of bread. That's a small act of compassion.
One example of courage is Ma Joad. She struggles against surmounting odds to keep the unity and integrity of the family in place. Her courage can't overcome all, though, as in the end she says, "Use’ ta be the fambly was fust. It ain’t so now. It’s anybody."
Jim Casy is the most courageous of the characters in The Grapes of Wrath as he becomes the Christ-like sacrificial victim for the cause of solidarity, the Oversoul of the migrant workers. Bravely, too, Tom Joad takes up his cross after Jim's death.
The quiet fortitude of Ma Joad is prevalent throughout the novel. She it is who holds together the family throughout by her example. One instance of this is her not telling the family that Grandma has died; instead, she sits quietly in the truck next to the dead woman until the family arrives at their destination.
All along the way, the Okies and other immigrants regularly show compassion for other people who are in need. They share what they can and do not condemn others for their unfortunate circumstances--as when a mother in the government camp is mortified that her daughters have "the skitters."
One character who shows compassion for these hard-working people who are being taken advantage of is Casey. He does not have his own family to feed, and in many ways he is nothing like the thousands of people who make their way to California hoping to make their lives better. Yet he actually loses his life trying to unite the workers so they can negotiate for better working conditions.
The most obvious example of love and compassion in the novel is the final scene between Rose of Sharon and the old man who she literally nurses back to health by breast feeding him. It is such an odd and kind of disturbing scene, but it stays with the reader forever. Rose of Sharon is only capable of the nursing because she was pregnant but lost the baby. She is heartbroken over the loss, but perhaps finds purpose in her situation. The great humanity of the scene is very powerful.
The book is really about courage, isn't it? The Joads and the others left the only life they had ever known for a completely different, unkown life. They stood up to corrupt bosses and unsavory characters. In the end, they stayed on their feet and true to themselves. As for compassion, I think that even in the stoic, harsh conditions they cared for each other.
Well, if you are looking for examples of courage, I would say you need to go no further than look at the Joad family and the tremendous courage that they display in all of the hardships they meet during their exodus and their hunt for work and their grim battle for survival. They are truly an example of tremendous courage and steadfastness in the face of so many trials and examples of lack of human compassion.