User blog comment:A.J AL/Season six plot hole./@comment-5619706-20121215033415/@comment-3481504-20121216021541

As stated by Samandriel, Angels can't horde or "use" Heaven's souls. And it's clearly a law articulated by Chuck, as Raphael didn't absorb them, but there's two possibilities why not--he's technically good in just wanting things to end as Scripture dictates, or he didn't see it necessary as he could beat whoop Castiel's butt.