The word "behold" alerts us to the introduction of the dead man into the story. Your language may have a way of doing this. Alternate translation: "there was a dead man who" (See: [[rc://en/ta/man/jit/writing-participants]])
This can be stated in active form. Alternate translation: "people were carrying out of the city a man who had died" (See: [[rc://en/ta/man/jit/figs-activepassive]])
"carried out. He was his mother's only son, and she was a widow. A rather large crowd." This is background information about the dead man and his mother. (See: [[rc://en/ta/man/jit/writing-background]])