To answer that difficult question, I’d like to share some thoughts from the book New Light on Depression by David Biebel, D.Min. and Harold Koenig, M.D.
“Family members, loved ones, and friends should encourage depressed persons—to get up in the morning, to go out to dinner, to go to a movie, to exercise with them, to do the things their depression is preventing them from enjoying, and to seek professional help if they are not doing so already. Once depressed people get out and start moving they often feel a lot better. Encouraging, however is not the same as forcing, manipulating, or cajoling, nor will arguing about it help much…Here, again, discernment is crucial so that your suggestions are made in the right way at the right time, to ensure the greatest likelihood that they will be accepted.
“One way to encourage a depressed friend to get out (and to get help) is to find a good depression support group and invite your loved one to attend it with you.” 
Biebel and Koenig identify “four helping patterns” they have seen Christians employ with their depressed family and friends-only one of which really helps. These are:
- Judging (“Your problem is caused by sin or lack of faith”)
- Giving advice (“Cheer up—things could be worse!”),i
- Identification (sympathizing so much that you get sucked into the pit of depression, too) and
- Empathy (suffering together with the person).
According to the authors “Only empathy really helps.”  Empathizers deeply feel the other person’s pain, without making it their own.
“The empathizer goes and gets a ladder, puts it in the pit, and climbs down to be with the depressed person until he or she is ready to climb out,” the authors say. “The key difference is that the empathizer has a goal in mind—not just to feel the depressed person’s pain, but to also act in a sense as a redeemer, willing to pay whatever cost there is in order for the other person to be healed…
“If you are really going to help your loved one through and beyond depression, the only way is to lay aside your rights, by choice, with the goal of serving that person’s best interests until he or she emerges into the light of day again.” 
Got a ladder? Put it down in your depressed loved one’s pit, climb down with them and pray for them until they can climb out.
Save me, O God, for the floodwaters are up to my neck.
Deeper and deeper I sink into the mire; I can’t find a foothold.
I am in deep water, and the floods overwhelm me.
I am exhausted from crying for help; my throat is parched.
My eyes are swollen with weeping, waiting for my God to help me…
Answer my prayers, O Lord, for your unfailing love is wonderful.
Take care of me, for your mercy is so plentiful.
Don’t hide from your servant; answer me quickly, for I am in deep trouble!
Come and redeem me; free me from my enemies. Psalm 69:1-3, 16-18
O LORD my God, I cried to you for help, and you restored my health. Psalm 30:2
 David B. Biebel and Harold G. Koenig New Light on Depression: Help, Hope, and Answers for the Depressed and Those Who Love Them (Grand Rapids, Michigan: Zondervan Publishing House), 2004, 233.
 Ibid, 246.
 Ibid, 248-249.
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