Death is a primary theme of the novel. When Robert Jordan is assigned to blow up the bridge, he knows that he will not survive it. Pablo and El Sordo, leaders of the Republican guerrilla bands, see that inevitability also. Almost all of the main characters in the book contemplate their own deaths.

Hotel Ambos Mundos, Havana, Ernest Hemingway's first residence in Cuba (1932-1939) where most of For Whom the Bell Tolls was written
A related theme is the vivid sense of camaraderie in the face of death and the surrendering of one's self for the common cause and the good of the people. Robert Jordan, Anselmo and others are ready to do "as all good men should" - that is, to make the ultimate sacrifice. The oft-repeated embracing gesture reinforces this sense of close companionship in the face of death. An incident involving the death of the character Joaquín's family serves as an excellent example of this theme. Having learned of this tragedy, Joaquín's comrades embrace and comfort him, saying they now are his family. Surrounding this love for one's comrades is the love for the Spanish soil. A love of place, of the senses, and of life itself is represented by the pine needle forest floor - both at the beginning and, poignantly, at the end of the novel - when Robert Jordan awaits his death feeling "his heart beating against the pine needle floor of the forest."
A companion theme to that of death is that of suicide. Many of the characters, including Robert Jordan, would prefer death over capture, and are prepared to kill themselves, be killed, or kill to avoid it. As the book ends, Robert Jordan, wounded and unable to travel with his companions, awaits a final ambush that will end his life. He prepares himself against the cruel outcomes of suicide to avoid capture, or inevitable torture for the extraction of information and death at the hands of the enemy. Still, he hopes to avoid suicide partly because his father, whom he views as a coward, committed suicide. Robert Jordan understands suicide but doesn't approve of it, and thinks that "you have to be awfully occupied with yourself to do a thing like that."[2] Robert Jordan's opinions on suicide may be used to analyze Hemingway's suicide 21 years later. Hemingway's father also committed suicide and it is a common theme in his works.
There also are the themes of political ideology and bigotry. After noticing how he so easily employed the convenient catch-phrase "enemy of the people", Jordan moves swiftly into the subjects and opines, "To be bigoted you have to be absolutely sure that you are right and nothing makes that surety and righteousness like continence. Continence is the foe of heresy."[3] Later in the book, Robert Jordan explains the threat of Fascism in his own country. "Robert Jordan, wiping out the stew bowl with bread, explained how the income tax and inheritance tax worked. 'But the big estates remain. Also, there are taxes on the land,' he said. 'But surely the big proprietors and the rich will make a revolution against such taxes. Such taxes appear to me to be revolutionary. They will revolt against the government when they see that they are threatened, exactly as the fascists have done here,' Primitivo said. 'It is possible.' 'Then you will have to fight in your country as we fight here.' 'Yes, we will have to fight.' 'But are there not many fascists in your country?' 'There are many who do not know they are fascists but will find it out when the time comes.'"[4]
Divination is another theme that arises in the book. Pilar, "Pablo's woman", is a reader of palms and more. When Robert Jordan questions her true abilities, she replies, "Because thou art a miracle of deafness.... It is not that thou art stupid. Thou art simply deaf. One who is deaf cannot hear music. Neither can he hear the radio. So he might say, never having heard them, that such things do not exist."