Asking a rhetorical question, Jesus encourages his audience to think carefully on what he says. His statement is a good example of a fortiori argument, otherwise known as a qal wahomer.1 In this form of argumentation what is true for a lesser thing is held to be true also for a greater.2 It is important to emphasize that with his question, Jesus is not advocating a carefree responsibility for his disciples, but he is saying that material necessities are not a valid cause for worry.3
25 C'est pourquoi je vous dis: Ne vous inquiétez pas pour votre vie de ce que vous mangerez, ni pour votre corps, de quoi vous serez vêtus. La vie n'est-elle pas plus que la nourriture, et le corps plus que le vêtement?