All debates on the existence of God are won by the atheists as far as I am concerned. The religious will never fail to retreat to the claim that one MUST have faith to believe because they can not furnish evidence or proof of God's existence. When asked who told them they must have faith, they say coyly, THE BIBLE! Well, the Bible is the thing in question in the first place, so it doesn't make sense to quote the Bible to prove that the Bible is true. Of course the Bible will say that the bible is true. Proving it is true entails looking at secular history and seeing how it adds up next to science. in this case, it is science not the Bible that proves or disproves the Bible is true. Until it is proven true, it can not be referred to at all, or the experiment is null and void. So, you can't say we must have faith, because that statement originates in the Bible, and the Bible is the thing in question. It is literally begging the question to say that.
The other retreat that religious people run to is emotional appeal, or appeal to emotion. One "JUST KNOWS" in this case that Jesus is true. When pressed to disclose HOW one JUST KNOWS, the religious person either doesn't know at all, or they describe, like my brother, some generic event like feeling warm and fuzzy one day, wile sitting in traffic, and that warmness or glow was Jesus. this kind of vague "proof" is fine for the person having it, but it doesn't help anybody else to know Jesus. In any case, it's so vague that it can't be DIS proven. So, again, the religious person is safe, retreated rather cowardly to the safety of their own un provable claims.