< ?php
function the_image($size = 'medium' , $class = ”){
global $post;
 
//setup the attachment array
$att_array = array(
'post_parent' => $post->ID,
'post_type' => 'attachment',
'post_mime_type' => 'image',
'order_by' => 'menu_order'
);
 
//get the post attachments
$attachments = get_children($att_array);
 
//make sure there are attachments
if (is_array($attachments)){
//loop through them
foreach($attachments as $att){
//find the one we want based on its characteristics
if ( $att->menu_order == 0){
$image_src_array = wp_get_attachment_image_src($att->ID, $size);
 
//get url – 1 and 2 are the x and y dimensions
$url = $image_src_array[0];
$caption = $att->post_excerpt;
$image_html = '<img align="left" style="padding:0 4px 4px 0" width="50px" src="%s" alt="%s" class="thumb-home"/>';
 
//combine the data
$html = sprintf($image_html,$url,$caption,$class);
 
//echo the result
echo $html;
}
}
}
 
}
?>

< ?php the_image('thumbnail','post-thumb');?>

......
<div class="entry">< ?php the_image('thumbnail','post-thumb');?>< ?php the_excerpt(); ?> </div>
......