A.T. Robertson Commentary Ephesians 4:15

"but speaking truth in love, we may grow up in all things into him, who is the head, [even] Christ;" — Ephesians 4:15 (ASV)

In love (εν αγαπη). If truth were always spoken only in love!

May grow into him (αυξησωμεν εις αυτον). Supply ινα and then note the final use of the first aorist active subjunctive. It is the metaphor of verse 13 (the full-grown man). We are the body and Christ is the Head. We are to grow up to his stature.