I follow the opinion that we can only eat the food if Allah's name has been invoked upon it (along with other necessary conditions), even if its sacrificed by Muslims, Christians or Jews. Is that correct? Considering the opinion I hold, my question is regarding eating food at some of our Muslim brothers' homes. We come across different situation in western countries that I am mentioning below.
1. We know about one of our Muslim brothers that he doesn't strictly care about the halal and haram food. If he invites us for a dinner, should we specifically ask him whether the food is halal or not, and refuse to eat if its not (this is what I think I should do). Or can we have a positive-thinking about our Muslim brother that he would have arranged halal food for us.
2. We know about one of our Muslim brothers that he considers the food of all the people of book as Halal (even without invoking Allah's name). What should be our approach in this situation. I have read that in case of difference of opinions in fiqh between Muslims, we should respect and follow the opinion of our Muslim brother who is hosting us. Does that apply in this situation too, such that we may respect and follow his opinion when we are at his home, and eat the food without hesitation (this is what I currently think I should do)?