Little help with a loop

Little help with a loop

I am trying to loop thru a json array of errors specific to a form #id (sel) but it is not working.

function setErrors(errors, sel){
    errorUpdate(sel);
    //alert(sel); // returns #add_form
    $(sel).each(errors, function(field, msg) {
        //alert(sel); returns nothing
        var parent = $('[data-field='+ field +']').parent();
        $('[data-field='+ field +']').addClass('form-error', function(){
            $(parent).append( '<span class="help-inline error-message">' + msg + '</span>' );
        });
    });
}

Any insight would be great.

Thanks,
Dave