It is tragic when well meaning believers loose their temper and start yelling over what the Bible has to say about a subject. These three Proverbs speak to the situation:
Proverbs 12:16, A fool’s wrath is known at once, but a prudent man covers shame.
Proverbs 13:16, Every prudent man acts with knowledge, but a fool lays open his folly.
Proverbs 20:3, It is honorable for a man to stop striving, since any fool can start a quarrel.
You see once the voices go up they cause the ears to shut down. You are not going to win people to Christ by yelling at them. Jesus never commanded us to go make converts. He said make disciples. Disciple willingly and lovingly follow Jesus. Converts are beat into submission and are still just as lost.
Back to yelling. Yelling your point does not work in any argument situation. Yelling your point about what the Bible teaches is a complete waist of good oxygen. You are not more right because you are louder. Strive to have calm discussions and if the other person is not understanding you try explaining it in a new way. If they want to yell just walk away and let it go.
Also remember that even though you may have believe in some minor item for 40 years you may actually be the one that is wrong. So approach discussions with humility. I have been a pastor for 15 years and God is still fine tuning my beliefs so they line up more with Him.