{As if I would terrify you by my letters} (h(9373) an ekphobein
humas dia t(936e) epistol(936e)). This use of h(9373) an with the
infinitive is seen in the papyri (Moulton, _Prolegomena_, p. 167)
and it is not an in the apodosis (Robertson, _Grammar_, pp.
974, 1040). The active of this old compound verb means to
frighten, to terrify. Here only in N.T. It is common in the LXX
( Job 7:14  33:16 ). Note plural (letters) here and cf.  1Co 5:9  2Co 2:3 .