Existential Threat - Enemy of Rational Discourse

I can be having a normal rational conversation with another person, and suddenly I respond with what seems like an over-blown emotional response.  One of the reasons that can happen is because they said something that I consider an "existential threat".  An existential threat is something that threatens my basis for existence or identity or the foundation that I have built my life on. 

According to Tim Keller, anger is love in motion toward a threat to what is loved, so if I feel angry, I can use that to learn what it is I love by examining what that person or idea threatens.

The operational identity / basis for existence of a real Christian is: God the Father is our foundation, Christ is our daily food (and he said his food was to do the will of His Father), and the Holy Spirit is our air supply (breath on me breath of life).  Our existence is founded on the "I Am" that was and is and is to come.  "My hope is built on nothing less..."

Based on the above, I should be able to talk more rationally about all sorts of topics without feeling threatened. 

• If people lie about ideas or even people I care about, such as my family, I can respond passionately with the truth, but need not be desperate, because those ideas are not my life, and my family is also defended by the same God.
• If people ruin my reputation I can and should be angry, but not in an oversized way, because that isn't my life support.  My name is written in the book of life.  
• If people question the existence of God, I want to correct them but not in a desperate sort of way because what others think about God is not what my life is based on.  It is based on His existence, which doesn't change.  
• If people even blaspheme the name of God or mis-characterize God, I will ask them to stop and defend the truth, but I need not destroy them, because I know God is real and He will defend His name (so actually objecting is an act of mercy toward the speaker and the other hearers).

The next time I feel an emotional response to something someone says, I need to ask the questions:

• What god am I defending?  
• What good is a god that needs my defense?