The whole explanation, Sirxxx, is exactly what arisart wrote.

Also, I was an advocate for Moria not only being alive when everyone said he had been eliminated, but also that he would return in the future, likely returned to his former stature of an imposing, fit pirate roaming the NW. Don't believe he'd become a part of Law or any one else's crew that we know though. He has too much pride for that, even if he was a dispicable, two-story, shadow-stealing leek the last time we saw him.