{I came out from the Father} (ex(886c)thon ek tou patros).
Definite act (aorist), the Incarnation, with repetition of ek
(out of), while in verse  27  we have para tou patros ex(886c)thon)
with no practical distinction between ek and para in
resultant idea. {Am come} (el(886c)utha). Perfect active indicative
of erchomai, as in  18:37 . The Incarnation is now a permanent
fact, once only a blessed hope ( 11:27 ). His leaving the world
and going to the Father does not set aside the fact of the
Incarnation. Both aphi(886d)i (I leave) and poreuomai (I go) are
futuristic present indicatives.