What do the Jewish burial rites reflect about the belief in God?
I think that there are some strong examples of how Jewish burial rites see death as part of a cycle where the divine is involved. Consider the invocation recited once someone receives news of death:
Barukh atah Adonai Eloheinu melekh ha'olam, dayan ha-emet.
The literal translation of such an invocation is the idea that God is the true force of definition and brings out the idea of being a "True Judge." This helps to bring out how practice and ritual in terms of death reflects the belief in God to a level of strength and absolute understanding about the nature of the divine in the face of mortality. The fact that the individuals who prepare the body for proper Jewish burial are those who are considered to be men and women of God. Also, consider that the body is cleansed and then covered with a prayer shawl, representing how the only artifact used to cover the dead body is something that has been closely associated with God. The recitation of the Kaddish is another example of how the process of death and mourning is so closely linked with God. In this, the belief in God is absolute, reflecting how the Jewish faith recognizes the issue of death as something that is dictated by God and how the rituals and rites that follow is are also ordained by God, needing to be carried out by human beings.
I would merely present one other element to enhance this discussion. Elie Wiesel's work Nightfeatures a great deal of detail about the process of death and the rites that are associated with it. In it, Wiesel argues that death and its rites are an extension of one's faith in God and an extension of what God asks of human beings. It is to this end that when a character, Akiba Drumer, is to leave for "selection," he asks his fellow prisoners to recite the Kaddish for him, reflection of how he sees members of his community as essential parts to enable him to experience a proper death, one that is sanctioned in the eyes of the divine. This reflects how the Jewish faith sees death and burial rites are linked to being divine ordinances requiring the submission of mortals for their execution.