Maintain proper and genuine emotion
Avoid fake, overly emotional tirades and preaching styles. Also avoid the other extreme; monotone and bland preaching. Speak from the heart in a genuine way that properly communicates the seriousness of the content and the concern you have for your hearers. We should be passionate in proclaiming this message, but our passion should be sincere and not a put on. If you don’t have genuine passion – get on your knees and sit in God’s presence until you get it!
This also becomes important as you learn to project your voice and maintain good volume without a) looking like a crazy person, or b) being so soft that no one can hear you.
“Be swift to hear and slow to speak” (James 1:19). People are much more apt to listen to you and consider what you are saying if you show a genuine willingness to do the same for them. Plus this helps you to understand them and avoids unnecessary confusion and miscommunication. This is also a great way to diffuse and disarm a loud heckler. Let them say what they have to say without trying to yell over them. When they feel like they are “being heard” they will calm down and you can either respond to their points or continue with what you were preaching. If they feel stifled by you preaching over them their frustration and anger will only escalate.
Use reason as well as simply proclaiming things
To simply declare something to be true is fine. But the human mind works in such a way as to desire a reason as to why “such and such” is true. When we are setting forth things that are not obvious truths then we owe it to those listening to “give a reason” (I Peter 3:15), If we don’t make sense then our message is worthy of rejection just as we would reject someone who made a presentation to us but couldn’t back up their claims with sound fact and reason. (ex. A Mormon knocking on your door, a telemarketer on the phone, etc…)
This entails that you study, exercise your mind, learn what you believe and why so that you are able to “convince the gainsayers” (Titus 1:9) and to “reason and persuade” (Acts 18:4, 19:8,) as is our Biblical example.
Answer questions honestly, answer them well
It is very important to be honest, don’t make stuff up or twist the facts to gain advantage in an argument. First, it is simply bad moral character and secondly, even if done from good intentions it can be a stumbling block to hearers if it is exposed. Sometimes you may simply need to say, “I don’t know”. Remember, no one likes a “know it all” attitude anyway.
Establish common ground, relate to hearers
Paul in Acts 17 used a religious monument and a poem of the Greeks to relate to them, establishing common ground whereby he could then communicate the gospel to them. This opens people up to you and establishes communication, something that is very difficult but very important to do for the open air preacher or street witnesser. I often times will use something on someone’s T-Shirt; a sports team or a music band, to connect with them. People want to know that we are real people with real life experiences and emotions. Phoniness or pretentiousness is very destructive to an effective witness.
Ask questions, frame the debate
Many times Jesus responded to a question with a question. Using questions does several things. One; it engages people personally, two; it gets people thinking, three; it helps to frame a subject or discussion.
Many unbelievers will ask loaded questions that cannot be answered with a yes or no answer. The Pharisees often did this to Jesus. He had the wisdom to respond with a question to re-frame the discussion. For example when asked should we pay taxes to Caesar, Christ responded by asking for a coin and then asked whose image was on the coin, thus re-framing the debate. Another example I use is when someone says, “Prove to me God exists?” I often will ask them in response, “What do you mean by prove? Can you define proof for me?” People will often ask for the type of proof for God that they don’t demand for lots other things they believe, thus exposing a bias in the way they evaluate the evidence for God’s existence and the truthfulness of the Gospel.