[Desdemona]

He obviously needs help and I wouldn't overtly mention God and Christianity, but talk to him. Make sure he knows that you are there for him. Whatever you do, don't abandon him or give him the idea that any sort of support system is lacking. Be kind and gentle.

I've known too many people who have lost family members in this situation to suicide mainly by abandoning them, including a couple of my own family members. Just don't abandon him.

[Canticle_of_Deborah]

He obviously needs help and I wouldn't overtly mention God and Christianity, but talk to him. Make sure he knows that you are there for him. Whatever you do, don't abandon him or give him the idea that any sort of support system is lacking. Be kind and gentle.

This is good advice.

A person in the grip of depression who is contemplating suicide is not thinking clearly, although they will surely think that they are. Having worked in psych nursing and knowing many therapists, I would caution you as to their overall effectiveness. I no longer have the confidence in that profession which I once did. Your brother may need mental health care as a first line response, but if his problem is in the spiritual/occult/demonic realm, medication or standard psych treatment will make him worse.

If at all possible, find a therapist now who has experience dealing with the occult. This experience will be necessary for long term treatment. Eventually, your brother will need spiritual guidance. In modern times the psychiatrist has replaced the priest with disastrous results. Start looking for a solid, conservative priest of good reputation.