How did the Holocaust affect people's faith?
Some people doubted God. Some lost their faith. Others thought
that it was a test from God and that they needed to pass it. during
the Holocaust itself, it caused confusion for some since they had
no idea what day it was and they were not able to know when the
religious times were. They had to guess and estimate.
A lot of Jews didn't lose their faith. Even in the worst times
in the ghettos and death camps, many kept on fufilling the Torah's
commands. It is well-known that they sang a song of Jewish belief
even when being marched to their imminent death.
Some saw in the Holocaust the striking fulfillment of
Torah-verses (see for example Deuteronomy ch.32).