"error_page" can not be used in the "return" of "if"

I am running nginx-0.7.61 on my FreeBSD box, and I have taken the 403
error page to a static html in server context as follows,

error_page 403 /my-403.html;

In my “if” condition of the same server context, I write:

if (my condition) {
return 403;

In my opinion, I want nginx returns my-403.html in this condition, not
the default 403 error page.

Can anyone tell me how to do this ?