The idea is that numerous Christian martyrs have suffered for their faith which indicates that there is something to that faith, because the martyrs thought it would be better to endure imprisonment, torture, and death than to renounce the faith or to worship a false god.
Stefan Molyneux’s response was as follows:
Remember a couple of years ago there were these guys who thought that the comet that was coming by was the mothership to heaven or something like that, and they cut their testicles off and then killed themselves to join that comet.
Well, if you are going to say that Jesus Christ is divine, because people died for him, then of course you are going to have to say that that comet is also divine, because people died for that. (podcast #13)
Now it is surely true that people have voluntarily suffered for communism, for the emperor, and for other objectionable causes. But not as many. “Tacitus is authority for the statement that an immense multitude… were put to death by Nero,” says the Catholic Encyclopedia. And not with such passion of conviction. And not for so long and in so many places, from Rome to Mexico to Japan. And, finally, not for a cause that has endured for two thousand years. These may be differences in degree, but the degree is considerable.
To get back to Stefan’s comet, the crucial difference between the two cases is that the Heaven’s Gate cultists committed suicide, while the Christian martyrs were murdered. It is an explicit Church teaching that one ought not to seek martyrdom. It’s a general opinion that suicide is a grave sin. So, the Christian martyrs wanted to continue living, but they were given a choice either to deny Christ or die. They would rather they were left alone and allowed to worship peacefully. The comet worshippers wanted a shortcut to heaven, while the Christian martyrs would rather have gone on with their lives.
In other words, there is, somewhat crudely, the supererogatory way to die (martyrdom, if the circumstances and one’s own judgment call for it), the right way to die (naturally), and the wrong way to die (suicide). Now it is true that suicide can be committed in a variety of creative ways. For example, one can pull a gun on a cop and have the cop shoot him in self-defense. (Such things have actually happened.) Perhaps there can be a suicide via upsetting the Roman emperor. Therefore, Christianity has nothing against trying as hard as one can to avoid both death and apostasy. If that is impossible, the decision which to choose is not legislated by any authoritative teaching but is left to the conscience of the individual.
It is true that both the martyr and the comet worshipper chose death. But for the former the choices were (1) renounce Christianity or (2) die; the opportunity to remain Christian and live was denied to him by his persecutors; whereas for the latter the choices were (1′) renounce the doctrine that committing suicide will lead to salvation or (2′) die; the choice to keep the “faith” and live was precluded as self-contradictory. The necessity of suicide was part of the core doctrine of the Heaven’s Gate cult; nothing like that is found in Christianity. Hence the Christian martyr suffered at the hands of the others’ intolerance and megalomania (such as when the Roman emperor wanted to be worshipped), while the Heaven’s Gate cultist suffered only from his own stupidity. Given that suicide is the wrong way to die, we can know with a degree of certainty that any religion that explicitly commands one to kill oneself to attain some benefits in the hereafter is false.
And so the comet worshippers are gone, while billions of Christians still practice their faith.