Error when approving comments??

Hi I just approved 5 comments and I got the below error. There seems to be some problem with the header code? What can I do to fix the problem.

Warning: Cannot modify header information – headers already sent by (output started at /home5/theoldfo/public_html/bequiablog/wp-config.php:47) in /home5/theoldfo/public_html/bequiablog/wp-includes/pluggable.php on line 391