Redirect to referring page after logging in

I’m not sure I understand your setup, but here are few ideas:

A) Display a login link with the redirect_to parameter set:

You could add the following to your custom template pages:

if( ! is_user_logged_in() )
{
    printf( '<a href="https://wordpress.stackexchange.com/questions/169704/%s">%s</a>', 
        wp_login_url( get_permalink() ),
        __( 'You need to login to view this page!' )
    );
}

This will generate a login link, for anonymous visitors, with the current page in the redirect_to GET parameter.

B) Redirect to the wp-login.php with the redirect_to parameter set:

Notice that the call to wp_redirect() must happen before the HTTP headers are sent.

We can call it within the template_redirect hook:

add_action( 'template_redirect', 
    function()
    {
        if( ! is_user_logged_in() 
            && is_page( array( 'member-page-1', 'member-page-2' ) ) 
        )
        {
            wp_safe_redirect( wp_login_url( get_permalink() ) ); 
            exit();
        }
    }
);

where we restrict the access to pages with the slugs member-page-1 and member-page-2.

C) The native login form (in-line):

Another option would be to include the native login form, directly into the page content:

add_filter( 'the_content', function( $content ) {

    if( ! is_user_logged_in() 
        && is_page( array( 'member-page-1', 'member-page-2' ) ) 
    )
        $content = wp_login_form( array( 'echo' => 0 ) );

    return $content;
}, PHP_INT_MAX );

where we restrict the access to pages with the slugs member-page-1 and member-page-2.

Notice you would have to take care of the archive/index/search pages.

Update: I simplified it by using the wp_login_url() function.