<h1>Edit post!</h1>
            <form name="feditpost" method="post" action="">
    <?php
                foreach($db->query("SELECT * FROM blog WHERE ID LIKE '$ID'") as $row)
                {
                    echo "Titel: <input type='text' size='50' name='titel' value='$row[titel]'><br>";
                    echo "Post:<br>";
                    echo "<textarea name='editblog'>";
                    echo $row[post];
                    echo "</textarea>";

                    echo "<input type='hidden' name='ID' value='";
                    echo $row[ID];
                    echo "'>";
                }
    ?>
                <input type="submit" value="Edit post" name="postedit">
            </form>
            <script>
                CKEDITOR.replace( 'editblog' );
            </script>
<?php
            if(isset($_POST['postedit']))
            {
                $titel = $_POST['titel'];
                $post = $_POST['editblog'];
                $ID = $_POST['ID'];

                $STH = $db->prepare("UPDATE blog SET titel='$titel',post='$post' WHERE ID=$ID");
                $STH->execute();
                echo "<h2>Post edited!</h2>";
            }