problem with has_post_thumpnail in foreach loop

I have a code that display the post if has_post_thumpnail the problem is it shows all the posts wheather it has thumpnail or not

    <?php
 global $post;
$args = array( 'numberposts' => 5 );
 $postQuery = get_posts($args);
 $num  = 0;
 foreach( $postQuery as $post ) : setup_postdata($post);

        if ( has_post_thumbnail() ) { ?>
        <div style="display: inline-block;; ">

                <a href="<?php echo get_permalink(); ?>" title="Go to <?php echo the_title(); ?>" rel="bookmark">
                    <?php the_post_thumbnail('medium'); ?>


                </a>
                </div>
                <div style="display: inline-block; width:50%; vertical-align: top;">
                <span style="vertical-align: top;" class="flex-caption"><?php the_title('<h1>','</h1>'); ?>

                    <?php the_content();  ?>
                    </span>
           </div>
        <?php 
        }
    endforeach; ?>