{With a rod} (en rabd(9369)). The so-called instrumental use
of en like the Hebrew ( 1Sa 17:43 ). The shepherd leaned on his
rod, staff, walking stick. The paedagogue had his rod also.
{Shall I come?} (elth(933b)). Deliberative subjunctive. Paul gives
them the choice. They can have him as their spiritual father or
as their paedagogue with a rod.