What does Kino mean when he says the pearl has become his soul?
Also asked, why does Kino come to feel that he will lose his soul if he gives up the Pearl?
The pearl is the only valuable thing left in his life and it has become the center of all of his goals and desires. If he loses it he feels he will have lost everything, After the pearl was found, Kino was filled with greed and wanted more than he needed and this destroyed is life.
Likewise, why does Kino want to keep the Pearl?
Kino hopes the pearl will prevent him from feeling that way again. His son will be provided with an education that will put an end to his neighbors being cheated by the educated townspeople. Kino sacrifices everything that matters to him in his desire to keep the pearl and get the best price.
Their friends put their needs in front of Kino's needs because they want to survive themselves. What does Kino say this time when Juana again says they should get rid of the pearl because it brings evil? What is implied in his answer? He says, "I am a man." He implies that he has to deal with it no matter what.