Kemmerich crying is one of the most disturbing moments from the early chapters of this book. It occurs in Chapter Two and happens as the narrator is trying to comfort and console Kemmerich as he faces death after having been wounded greviously in battle. Note what the narrator says about Kemmerich and his tears, and how this sight is so upsetting for him as well:
What if he were to open his mouth and cry out! But he only weeps, his head turned aside. He does not speak of his mother or his brothers and sisters. He says nothing; all that lies behind him; he is entirely alone now with his little life of nineteen years, and cries because it leaves him. This is the most disturbing and hardest parting that I have ever seen...
Kemmerich therefore cries because of the way that he is left alone with the knowledge that he is dying and that there is no escape from this future, or this lack of a future, for him. There is no hope of any survival from this situation, and he is only left to dwell on his "little life of nineteen years" as he slowly sinks away from life and into death.