Either your friend is joking or he is in need of mental help. There is such a thing as multiple personality disorder that would in fact result in the same behavior.
I find that people that are not sound of mind are indeed more spiritually attuned and this can confuse people and make them think the situation is 100% legitimate. But the truth of the matter is, their mind warps their reality, whether physical or spiritual. So although their instability helps them to experience things more readily (due to absence of natural mental filters), it equally prevents them from perceiving things clearly. That part of our mind that says "hey, this seems too fantastical" isn't working with them. And since the spiritual is far easier to warp with thought/emotion than the physical, it tends to get out of hand. If he is involved in magick he should stop before he hurts himself or others and should only focus on protection until he is in a healthier state of mind.
My best advice to you is to ignore this behavior of his directly but discuss it with his family. If it is a joke, it will definitely bite him back. And if it is not, you are doing him a favor by letting his family know about a potentially serious problem.