The family structure is dysfunctional and broken, which resonates with a lot of American families. The break down resulted from the father abusing alcohol and also abusing the family as a result. So, bitterness has truly built up in the hearts of his sons. Each son, Tommy and Brendan, sought to break free from the abusive family. One son started his own family, while the other served as a Marine. Their paths separated for a significant time, until they were reunited by an underlying passion for MMA.
The plot of Warrior allows viewers to watch the lives of Tommy and Brendan merge once again. They are brothers by birth, but not by true relationship and friendship. Both have been hurt by their father, and so there is not figure there to look to for guidance in mending their relationship. As their lives merge, Tommy jars against the idea of having a brother. He felt that Brendan had already forsaken him. Even before they got into the ring they already began dueling.
Brendan represents hope and light in the movie. He is the underdog and at the end the unsung hero. For the sake of his family he sought to win the SPARTA competition, and he ended up redeeming more than just money so he and his family could live. He redeem his relationship with his brother. Brendan was hopeful for Tommy from the beginning, and in the end he was their to carry his broken body. Brendan incarnates Christ's role of reconciliation and redemption. No matter how hard Tommy fought Brendan still cared about the well being of his brother, despite his rejection.
The overarching theme is redemption. Think about the last image was left in the mind of the viewers. Brothers at odds carrying one another's broken bodies from the fighting ring. They went to abusing one another for their own sake to solely focusing on the needs of one another, specifically Brendan to Tommy.