Let's start with his assertion that the question of God is the most important question we can ask - if Christianity is true.
Yes, Christianity appears as a threat against the other religions, “Follow our ways or go to hell,” as the Bible warns repeatedly of the worst fate for unbelievers. “The ways” of Christians amount to an indirect interpretation by Paul and committees, to assertions by Jesus that should have been understood to be vague from the very beginning. Indeed, the first century Christians should have noticed immediately that if Jesus was God then He deliberately chose to give a weak, noninvasive teaching, not genuine, careful guidance.
Everyone who denies Christianity, insofar as they are aware of the threat this religion makes against all other religions, should notice they are standing against the settled opinion of two billion Christians. Of course also, many Christian sects believe the other sects are damned. In fact this becomes one of the proofs that the two billion are wrong, that this idea “the others are damned” is somehow being generated from native human hatred. The Christians are not united against the other religions, and whatever Jesus said, the humans are not able to come together behind Him, without damning other Christians.
To stand against the edifice of the religions and feel secure is not easy, if you have awareness of the myriad humans you stand against, and some respect for the human intellect. In general those opposing the religions are not seeing what they are opposing, telling themselves merely “those other people are worthless,” ignoring the teeming masses of doctors, lawyers, scientists and professors, who adopt religion. Yet a secure position can be found if these teeming masses are indeed found worthless, though not in the sense anyone is expecting. Human technology is ferocious; personality not so much.
It’s possible God could set up a religion saying, “Follow it or perish in everlasting fire.” To neutralize the threat of the Christians, it can be shown Christianity is not such a religion. The key is that Jesus set up no meaningful standards, only very vague ones. You can’t disobey if God didn’t tell you what He wanted (at least) and the reasons for it (at best). Nobody can follow Jesus, because He didn’t say anything that has a clear and obvious interpretation. If Jesus was leading nowhere, then His was not a saving religion.