Cuphead - literal what

"…you know, I've been working for the Devil for quite a while. Can hardly remember when he actually took me under his arm. I've seen a lot, down there and in this casino, so much that even things to be seen once-in-a-lifetime, men winning and losing everything in a single night, the sort of celebrations and excesses that'd kill weaker folks, all of that hardly gets a blink nowadays.
Suppose that what I want to say here is, and excuse my French, for the first time in over a century, I'm fucking speechless."