en_tn/1jn/02/11.md

is in the darkness and walks in the darkness

Here "walk" is a metaphor for how a person lives or behaves. Here to be "in the darkness" and "walks in the darkness" mean the same thing. This brings attention to how evil it is to hate a fellow believer. AT: "does what is evil" (See: rc://en/ta/man/translate/figs-metaphor and rc://en/ta/man/translate/figs-parallelism)

he does not know where he is going

This is a metaphor for the believer who is not living as a Christian should be living. AT: "he does not know what he should do" (See: rc://en/ta/man/translate/figs-metaphor)

the darkness has blinded his eyes

"the darkness has made him unable to see." Darkness is a metaphor for sin or evil. AT: "sin has made it impossible for him to understand the truth" (See: rc://en/ta/man/translate/figs-metaphor)