The theory seems to be that as long as a man is a failure he is one of God's children, but that as soon as he succeeds he is taken over by the Devil.

The quote "The theory seems to be that as long as a man is a failure he is one of God's children, but that as soon as he succeeds he is taken over by the Devil" by H. L. Mencken presents a satirical commentary on the way society often views success and failure in moral or religious terms. Mencken suggests that society may see failure as a sign of humility and virtue, associating the unsuccessful with purity or righteousness. However, once a person achieves success, they are often viewed with suspicion, as if their accomplishment somehow makes them morally compromised or influenced by greed or pride.

Originating from H. L. Mencken, an American journalist and social critic known for his sharp wit and critique of societal norms, this quote plays on the contradictions in how people are judged based on their economic or social status. Mencken is pointing out the irony in how success can lead to a negative view, while failure is often romantically linked with innocence or moral goodness. This commentary challenges conventional views of morality and success, questioning why one is seen as virtuous and the other as corrupt.

Mencken’s use of the idea that success leads to being "taken over by the Devil" is a metaphorical way of highlighting how society often vilifies the successful, suggesting that they have lost their humility or sold out to materialism. In contrast, the failure is often treated with sympathy and even reverence, regardless of the circumstances. This view reinforces the idea that social values can be inconsistent and that success often brings with it a complex set of judgments and assumptions.

Ultimately, the quote serves as a critique of how success and failure are perceived in society. Mencken uses his typical satirical style to point out the moral contradictions in how people are judged based on their achievements or lack thereof, suggesting that societal views on these matters are not always rational or fair.