Passage
But ye did not so learn Christ;
But ye did not so learn Christ;
Ephesians 4:18 being darkened in their understanding, alienated from the life of God, because of the ignorance that is in them, because of the hardening of their heart;
Ephesians 4:19 who being past feeling gave themselves up to lasciviousness, to work all uncleanness with greediness.
Ephesians 4:20 But ye did not so learn Christ;
Ephesians 4:21 if so be that ye heard him, and were taught in him, even as truth is in Jesus:
Ephesians 4:22 that ye put away, as concerning your former manner of life, the old man, that waxeth corrupt after the lusts of deceit;
The verse centers on "learn" and "christ". It is saying that the verse draws attention to "learn" and "christ", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 19's "who being past feeling gave themselves up..." into verse 21's "if so be that ye heard him...", so "learn" and "christ" belong inside that flow. In Ephesians context, the local focus is grace, union with Christ, the church, and new creation.
A plain takeaway is to answer the verse's own emphasis on "learn" and "christ" with trust shaped by these words, not by a vague optimism outside the passage.