Let's start by finding Apache's error log.
configfile where it's saving the logs to:
grep ErrorLog /etc/apache2/httpd.conf
# ErrorLog: The location of the error log file. # If you do not specify an ErrorLog directive within a <VirtualHost> ErrorLog "/private/var/log/apache2/error_log"
Fatal error. Yours might be slightly different, but the overall message is the same.
[Sun Sep 11 22:10:31 ...