gengwall

Just one reference on the perfect tense in ancient Greek.

“The perfect tense expresses perfective action. Perfective action involves a present state which has resulted from a past action. The present state is a continuing state; the past action is a completed action.”

(SYNTAX OF NEW TESTAMENT GREEK, James A. Brooks, Carlton L. Winbery, University Press of America, Lanham, Md., 1988, pp. 104-5 as referenced on http://www.biblestudymanuals.net/new_testament_greek.htm)

In this case, the past action was the deception and the continuing state is the transgression (false teaching) which resulted from that deception.