From Chapter Eight, Why You Don't Always Have to Experience Joy: Or, How God Vindicates the Afflicted.
[Job's three friends] did better when they did nothing. That's a hard lesson to learn, but it's indispensable for anyone who really wants to comfort the afflicted. Sometimes there is nothing we can do to comfort them, and this itself is a form of suffering that is hard for us to bear. But it is also a way that we enter into their suffering and share it. It is essential to the work of sympathy and compassion -- both of which are old words meaning to suffer with someone. And it is hard work to sit in silence and listen to someone we love groan and cry and say dreadful things about God. Sometimes the most we can do to relieve their suffering is just hear their awful words and bear with them patiently. This is the cross of listening, a cross Job's friends were unwilling to bear. They thought they had to do something about his awful words.