in this post i m showing you how to display your any posts’s featured images in anywhere in your site. try below code.
global $post; // globally defined $post;
$smitcky_image = wp_get_attachment_url( get_post_thumbnail_id($post->ID) );
<img src="<?php echo $smitcky_image";?>" title="Wordpress Featured Image"/>
in above code you can directly pass your post id instead of $post->ID. $post->ID is getting your current post id automatically.