Have him try sublime text 2, it's not specialized for lisp, but there's probably plugins for lisp and it's easily extendable via python if he knows python, so i

Have him try sublime text 2, it's not specialized for lisp, but there's probably plugins for lisp and it's easily extendable via python if he knows python, so it's fairly decent. I guess it depends on how much he plans to use lisp though. If he plans on using it a lot then learning emacs would be a good investment for him.