Bulletproofing apologetics is a practice that I have developed over the years that makes my apologetics much more effective. I discuss it in my course Beginning Apologetics.
The basic principle involves removing everything that is a distraction or that is weak—i.e., everything that isn’t “bulletproof.”
Find Common Ground: No matter who you are dealing with, you will agree with them about some things. Thinking about and consciously identifying that common ground will improve your apologetics.
Don’t Waste Time: By identifying common ground, you can avoid wasting time arguing about things you agree on. They may not phrase things exactly the same way, but you don’t want to be distracted by that.
As Paul says, we don’t want to dispute about words, which “only ruins the hearers” (2 Tim. 2:14). He even says that those who do have a “morbid craving for controversy” (1 Tim. 6:4).
We thus should move on from areas where we have merely a semantic disagreement and look at ones where we have substantive disagreements. By doing so, you also show that you really care about substance and not nitpicking modes of expression.
Show Goodwill: By finding—and acknowledging—common ground, you also show goodwill toward the person you are serving, just as Paul did when he spoke to the men of Athens, complimenting them on their religiosity (Acts 17:22). This helped him build a bridge to them, which then helped him correct false ideas they had.
Find Productive Areas of Discussion: To find productive areas of discussion, we also should identify areas where we have too much substantive disagreement to make them worth talking about at present.
For example, in the early Church there was a heresy that held Christ has only one will. It was known as Monothelitism (Greek, monos, “one,” thelêma, “will”). The true position is Dyothelitism (Greek, duo, “two”), which holds that Christ has two wills—one divine and one human, since he is fully God and fully man.
In the early Church, it would make no sense to discuss Dyothelitism with an Ebionite, since Ebionites believed Jesus was just a man and thus had no basis for believing that he has a divine will in addition to a human one.
The logical thing to do would be to back up a step and talk about Jesus’ divinity. One would need first to convince an Ebionite of Jesus’ divinity before it would be sensible to discuss how many wills Jesus has.
Similarly, today it makes little sense to try to prove certain Marian doctrines, such as the Immaculate Conception or the Assumption, for Protestants, who hold the principle of sola scriptura.
The primary support for these doctrines comes from Tradition rather than Scripture, and so one needs to accept the role of Tradition before they can be proved. Consequently, the logical thing to do is back up a step and discuss the role of Tradition.
Distinguish Opinion from Church Teaching: In our apologetics, we need to clearly distinguish matters of personal opinion from Church teaching. If something is not an official doctrine of the Church then the Church does not expect people to believe it, and we should not lead people to think that it does. To do so would misrepresent the Church.
For example, it has been a very common theological opinion that, because animals lack rational souls, they do not have an afterlife. However, this is not a Church teaching.
Consequently, if one is doing apologetics with an animal rights activist or someone (perhaps a child) who is very attached to their pets, it could place a barrier between them and the Church to insist on the common theological opinion when the Church does not require them to accept it.
Remove Weaker Arguments: As the saying goes, “Less is more.” It is much more convincing to give a person one convincing argument rather than ten lesser arguments.
Not only will data dumping exceed their attention span and cause them to stop thinking about the arguments and become frustrated with you, it also will give them a way to evade the force of your arguments.
In any large collection of arguments, not all will be of equal strength, and the person you are trying to serve will spot this fact. He will find himself thinking about the fact that some of your arguments aren’t convincing, and he can dwell on that fact and ignore the force of your better arguments.
By peeling away the weaker arguments and not presenting them, you give the person no alternative but to consider the force of your best arguments, making them more effective.
Remove Snark: A final but crucial step in bulletproofing is to remove all of the snark.
It can be extremely tempting to be snarky about viewpoints we disagree with and the people who hold them. This is a human failing, but it needs to be resisted. It adds heat rather than light to discussions.
If you are snarky when dealing with someone—whether it is face-to-face, online, or in print—he will start thinking about the fact that you are being snarky with him and this will distract him from the force of your arguments.
In conversations, you need to develop an internal filter to keep you from phrasing things in a snarky manner, and when writing, you need to go back over what you’ve written and remove the elements of snark.
Kindness and compassion will get a person on your side and allow him to think about your arguments open-mindedly.