It's possible you're thinking of a poem or song that references the Treblinka extermination camp. However, without a specific title or author, I cannot provide you with a theme.
If you can provide more information about the poem you're looking for, such as the author or a few lines from the poem, I can help you identify the theme.
In general, poems and songs that address the Treblinka extermination camp often explore themes of:
* The Holocaust: The horrors of the Nazi genocide, particularly the systematic extermination of Jews.
* Loss and grief: The immense loss of life and the suffering of those who were murdered.
* The fragility of life: The sudden and brutal end of innocent lives.
* Humanity and inhumanity: The capacity for both good and evil in human nature.
* Memory and remembrance: The importance of remembering the past and honoring the victims.
* Hope and resilience: The strength of the human spirit and the ability to overcome adversity.
Please provide more context, and I will be happy to help you understand the theme of the poem you're interested in.