<?php
$is_checked = ""; 
if($aaa['odev1'] == 1){
$is_checked = "checked";
}
?>

                Kelime-i Şehadet  
                <div class="col-xs-3"> 
                    <label> 
                        <input type="hidden" name="odev1" value="2"   /> 
                        <input type="checkbox" name="odev1" value="1"  <?php 
 echo $is_checked; ?>>  
                        <span class="lbl"></span> 
                    </label> 
                </div>