If an atheist has a weak explanation of religiosity, perhaps that atheist gets infected with religion.

It shouldn't come as great revelation, to an atheist, that to those infected with a mind virus it "feels cringe" when anything attacks the virus. That's its whole mechanism of action, its fangs. Besides, there's things like faith healing, and gospel churches, and the phrase "religious ecstacy", and all these other signs of the religious getting off on religion, so it should be obvious that they're defending something that feels precious, and are not merely terrorized.

However, if the atheist instead made a shallow assumption that religiosity is simple fear of a smiting bogeyman god, then it would come as a revelation that the religious are in fact having euphoric feelings, and this might be mistaken by the now ex-atheist for divine revelation of the way and the truth and the light, as the fangs sink in.