Was teaching. Won’t immediately. Clearly meaning those lessons were aborted for the very sensible reason of Ellie’s disappearance, so Stephen shoots him a dubious look. And really it’s the most predictable thing in the world when the man’s immediate response is both helpful and mildly chiding:

“Well, then we’re resuming them. Jesus christ, Mobius, you were on a ship just last summer, what if you’d fallen overboard?”