|From The Sting.|
Now the sting of death is sin: and the power of sin is the law. (1 Cor. 15:56)
Without sin, there is no death. Death is emptied of its sting.
And "the power of sin is the law". This is true when the law is extrinsic and not intrinsic. Our relation to the law as sinners is one of shame and anger, for we are unable to fulfill it.
Therefore, the single most likely cause of people arguing with you and getting mad at you if you're somehow preaching the Christian Faith is a bad conscience, their bad conscience. It stings. Stings like the sin they are guilty of, the sin which finds its shape by the light of the law. The sin which, they know in their hearts, leads to death.
And when the law sheds light on this, we sinners cower back in our holes and seek the darkness.