Passage
[namely] your having put off according to the former conversation the old man which corrupts itself according to the deceitful lusts;
[namely] your having put off according to the former conversation the old man which corrupts itself according to the deceitful lusts;
Ephesians 4:20 But *ye* have not thus learnt the Christ,
Ephesians 4:21 if ye have heard him and been instructed in him according as [the] truth is in Jesus;
Ephesians 4:22 [namely] your having put off according to the former conversation the old man which corrupts itself according to the deceitful lusts;
Ephesians 4:23 and being renewed in the spirit of your mind;
Ephesians 4:24 and [your] having put on the new man, which according to God is created in truthful righteousness and holiness.
The verse centers on "namely", "having", "former", "conversation", "corrupts", "deceitful", and "lusts". It is saying that the verse draws attention to "namely" and "having", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 21's "if ye have heard him and been..." into verse 23's "and being renewed in the spirit of...", so "namely" and "having" 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 "namely" and "having" with trust shaped by these words, not by a vague optimism outside the passage.