This is not the way it should be!
Especially when the argument is between two Christians and at least one of them is a proponent of a harsh doctrine, such as excluding minority or outcast groups – say homeless or gay people – from Church. Because then, those outside see the harsh attitude – and the way even we more gentle, Grace-believing people respond – and project that onto our loving Heavenly Father. “If that’s how those people represent their god”, they think, “I want nothing to do with him, because if he’s anything like his ‘people’ then he’s not worth bothering with”.
And, given the data they are working from, I would tend to agree. But God is not like that, and we need to find better ways of interacting with others in a non-judgemental fashion. Only in that way can dialogue be maintaned without its breaking down into vitriolic rhetoric.