I first read this article by Roger Nicole, entitled How to Deal with Those Who Differ from Us, several years ago and have lately turned to it afresh. It's chock full of sound biblical wisdom from a senior theologian.
He writes: "In order to approach this subject, there are three major questions that we must ask; and I would like to emphasize very strongly that, in my judgement, we need to ask them precisely in the right order: (1) What do I owe the person who differs from me? (2) What can I learn from the person who differs from me? (3) How can I cope with the person who differs from me?"
I encourage you to read the whole thing!