Asalamu alaykum, Obviously, as muslims, we find his conversion away from Islam to be abhorrent. But, there should be a level of hikma a muslim should utilise if they want to guide somebody back. Your post is only likely to further him away from Islam. I mean, take the imam Silouan is talking about. He actually invited him to dinner and had a long discussion to guide him with hikmah and patience. That's what we should be like too. Harshness in this context is counter-productive and if your intention is sincere, you shouldn't do it.