In The Bronze Bow, how does Daniel's view of Rosh change during Chapter 18?

Daniel initially joined with Rosh because he thought the bandit leader could offer him something that he desired: revenge. Daniel assumed that Rosh was working for the cause of freeing Israel from Roman occupancy, because his criminal activities often worked against Roman interest. In fact, Rosh has always been a criminal, working entirely for himself, and he used the cause of freedom as a way to further his own interests. Daniel finally realizes this when Rosh refuses to help him rescue Joel.

The red mist of anger cleared suddenly from Daniel's mind. He looked at the man who had been his leader. He saw the coarsened face with its tangle of dirty beard. He saw the hard mouth, the calculating little eyes. He saw a man he had never really looked at before."The cause!" he said with despair. "How could you know what it means?"
(Speare, The Bronze Bow, Google Books)

Joel is Daniel's friend, one who has helped him rediscover his own humanity and his capacity for love. To Rosh, however, Joel is simply a pawn to be used and discarded when he is no longer of use. Sacrificing men to save him on moral grounds -- which is exactly what Daniel does later -- is alien to Rosh, since he cares about nothing except for his own survival and comfort. Daniel finally realizes that Rosh has been using him since day one, with no actual concern for the cause itself.

In The Bronze Bow, how does Daniel's perception of Rosh change in Chapter 18?

Rosh has lived in the hills for years, stealing from merchants and caravans, and recruiting from those who wish to fight the Romans. He claims to be on the side of Israeli independence, and that is what attracts Daniel to his band. Daniel, however, is a true patriot because of his desire for revenge; while he sees Rosh as a father figure and an inspiration, he realizes when Rosh refuses to help rescue Joel that the only thing Rosh cares about is himself.

In another moment Rosh would spring at him... He could not fight with Rosh. The very strength of his hands he owed to this man. And what good would it do Joel? He turned away without speaking, and passed through the ring of silent, wary men. He knew that he was through with the mountain for ever.
(Speare, The Bronze Bow, Google Books)

This is a turning point for Daniel, who discovers that his friendship with Joel is more important than his need for revenge. If he stayed with Rosh, he could eventually battle with the Romans, but at the cost of Joel's life. This realization leads him to leave Rosh and form his own group, one dedicated explicitly to freeing Israel. Without that turning point, Rosh's self-interest would probably have continued to influence Daniel until he no longer cared about his cause, but instead cared only for himself.

When and why did Daniel break from Rosh in "The Bronze Bow", and how did he perceive Rosh's true self?

Daniel finally makes the break from Rosh when Joel is captured while doing what Rosh has ordered and Rosh refuses to do anything to try to rescue Joel.  In fact Rosh shows absolutely no concern for Joel at all.  Daniel becomes very angry and Rosh, in turn attacks Daniel for having a "soft streak."  This is it for Daniel.  He has finally seen that Rosh is just a selfish man who really attacks the Romans for his own glory not to save Israel.  Daniel leaves and organizes an a rescue party for Joel. The attemp rescues Joel but several others are killed by the Romans. 

How does Daniel's treatment of Rosh change from the beginning to the end of The Bronze Bow?

At the beginning of The Bronze Bow, Daniel is very loyal toward Rosh and treats him as his hero. When he tells Joel about Rosh, he says he is a good man and the bravest man in the world. Daniel obeys Rosh's commands when he orders him to take care of Samson and when he assigns him to steal from the miser. He respectfully asks Rosh if he can go to Capernaum to try to recruit Joel to their cause. Chapter 8 states that Daniel "worshiped and feared Rosh." When Rosh gruffly orders Daniel to fix his favorite dagger, Daniel obeys, and when he moves to the village, he creates a band of men to be Rosh's army there. 

However, in chapter 17, Rosh has been making raids on the homes of the villagers, stealing from fellow Jews like a mere bandit. Although Daniel wants to remain loyal to Rosh, he sees that the people are turning against him. In chapter 18, Joel is captured by Romans while performing undercover work for Rosh. Daniel goes to Rosh to ask him to rescue Joel, and Rosh refuses. At that point, Daniel disagrees with and argues with Rosh outright. Finally he says, "I am not one of your men. Not any longer." He leaves the mountain and Rosh forever at that point.

Why does Daniel leave Rosh's group in The Bronze Bow?

Daniel's disillusionment and break with Rosh have been slowly building as Daniel becomes aware of Rosh's selfishness and coldness. Rosh eats mutton, for example, while his men go hungry, and he encourages his men to steal from other Jews.

Everything comes to a head, however, when Daniel learns that the Roman centurions have arrested Joel. Daniel is fearful about what will happen to his loyal friend and follower. He instinctively turns to Rosh for help, thinking his leader will be concerned and have a plan.

Daniel is shocked at Rosh's indifference. Rosh has no interest in helping Joel and accuses Daniel of being weak because of his attachment to other people. The scales fall from Daniel's eyes, and for the first time he realizes fully that he is seeing the true man, one he “had never really looked at before.”

Although Daniel shares Rosh's desire to rid Palestine of the Romans, he can no longer follow a man of such a low character as Rosh. Rosh is wedded to violence and is callous, crude, and lacking in empathy. Daniel, especially now that he has learned and experienced more from Jesus, recognizes that Rosh is little more than a thug. At this point, Daniel leaves Rosh to go his own way, taking on the mantle of leadership.

In The Bronze Bow, does Daniel like Rosh?

In The Bronze Bow by Elizabeth George Speare, the relationship between Daniel and Rosh changes over time. At first, Daniel sees Rosh as a bold and fearless leader who will help the community in the fight against the oppressive Romans. Rosh trains Daniel and Daniel follows him and makes excuses or finds reasons for when Rosh's actions are less than heroic. This is not only because Daniel looks up to Rosh, but also because of their mutual hatred for the Romans, who crucified Daniel's father and from whom brutality is an everyday occurrence. This bod begins to crack as Rosh continually steels from the Jewish community claiming that they should be happy to help him. When Rosh refuses to help a close friend of Daniel's who was captured risking his life to help Rosh, Daniel realizes that Rosh is only a violent, selfish criminal using the Roman oppression to excuse his actions. Daniel leaves Rosh's band and the link between them is severed.

Why does Daniel reject Rosh in The Bronze Bow?

When Daniel first meets Rosh, he believes that he has found the perfect leader. He admires the rebel insurgent and wants to believe that he is indeed the messiah. Daniel's entire personality is based upon his hatred of the Romans. He has watched his father and uncle be crucified by them and has seen his little sister succumb to madness due to their heinous acts. Rosh gives Daniel the means to kill as many Romans as he can, and this is more than enough for Daniel to live meaningfully.

However, Daniel eventually begins to have his heart changed by seeing Jesus and his message of kindness. While Jesus understands Daniel's feelings, he insists that violence simply begets more violence, and that love is the only true way to change the world. In time, Daniel rejects the dogma of Rosh and makes the change to follow Jesus.