A.T. Robertson Commentary 1 Corinthians 13:12

"For now we see in a mirror, darkly; but then face to face: now I know in part; but then shall I know fully even as also I was fully known." — 1 Corinthians 13:12 (ASV)

In a mirror (δι' εσοπτρου). By means of a mirror (εσοπτρον, from οπτω, old word, in papyri). Ancient mirrors were of polished metal, not glass, those in Corinth being famous.

Darkly (εν αινιγματ). Literally, in an enigma. Old word from αινισσομα, to express obscurely. This is true of all ancient mirrors. Here only in N.T., but often in LXX. "To see a friend's face in a cheap mirror would be very different from looking at the friend" (Robertson and Plummer).

Face to face (προσωπον προς προσωπον). Note triple use of προς which means facing one as in Joh 1:1. Προσωπον is old word from προς and οπς, eye, face.

Shall I know (επιγνωσομα). I shall fully (επι-) know. Future middle indicative as γινωσκω (I know) is present active and επεγνωσθην (I was fully known) is first aorist passive (all three voices).