What a caring co-worker you are!And all of your co-workers, if all they have reported is an 'eerie feeling' no one has launched into names, verbal attacks, sounds like you have a very mature workplace, how refreshing, because people often come here with quite the opposite report, when they have issues at work......

Could you recommend this website to him? Explain that there are things a psychiatrist can do that a Chrisitan counselor cannot? Show him some literature about mental illness, you could say you have a family member or friend that also has it, as a way of showing understanding?