<div id="myModal38" class="modal fade" tabindex="-1">
<?php $args1 = array(
                    'post_type' => 'post',
                    'category_name' => 'modal',
                    'posts_per_page' => '1',
                );
    $modalPost = new WP_Query( $args1 );
    if( $modalPost->have_posts() ) :
?>
    <div class="modal-dialog">
    <?php while ( $modalPost->have_posts() ) : $modalPost->the_post(); ?>
        <div class="modal-content">
            <div class="modal-header">
                <button class="close" type="button" data-dismiss="modal">×</button>
                    <h4 class="modal-title"><?php the_title(); ?></h4>
            </div>
            <div class="modal-body">
                <?php the_post_thumbnail(); ?>
                <?php the_content(); ?>
    <?php endwhile; ?>
            </div>
    <?php endif; ?>
    <?php wp_reset_postdata(); ?>
            </div><!-- /.modal-content -->
    </div><!-- /.modal-dialog -->
</div><!-- /.modal -->
<!-- Modal -->