User blog comment:B214/Talk About What You Want! 2/@comment-24098614-20140711102904/@comment-1359322-20140711110650

The God being open minded, doubtful on that. During the speech, given by Michael in Volume 4,

"“…….I have lost a lot of things. However, there’s no helping seeking for things that aren’t present. It is our duty to guide humans. We members of the Seraph have the same opinion that the most important thing is to watch over the children of God from now on as well, and to guide them.”"

Azazel's reply

"“Hey hey, with your speech just now, you’ll ‘fall’ you know? -I thought that but you took over the system, right. It’s become a good world. It’s completely different from the time when we ‘fell’.”"

Meant that the speech Michael gave would have made Michael become a Fallen Angel if God was still alive, how's that open minded.

In the end, it was Cao Cao's own undoing, he constantly mentioned about being a human yet he used the Medusa's eye. Remember the truth idea sucks the ambition of the user, meaning it took in Cao Cao's will and determine that Cao Cao who used the Medusa eye is going against his own ambition of being a "human" hero. On the other hand, Issei's dream is to become the "hero of the children of the Underworld". Issei didn't do anything that went against his dream like Cao Cao did with his ambition, thus was accepted while Cao Cao was rejected.