I was reading the first part of an NT book just for whim. To see how far I can go before I get knocked down. :)
Th=? e)pau/rion pa/lin i(sth/kei )Iwa/nhj kai\ e)k tw=n maqhtw=n au)tou= du/o,
Attic pluperfect, 3rd. sg. of i(/sthmi is ei(sth/kei. Perseus has no morphological link for this occurrence. Is it a common variation in koine?