help pls

Catchable fatal error: Object of class WP_Error could not be converted to string in /home/orizonto/public_html/test/wp-content/themes/Soon/lib/custom.lib.php on line 157

i want to use theme SOON .hovewer my images don’t show up at HOME page.
how can i fix this problem .i have beeb trying every thing untill now. pls helpppppp