en_tn/1jn/05/16.md

his brother

"a fellow believer"

life

The word "life" throughout this letter refers to more than physical life. Here "life" refers to being alive spiritually. See how you translated this in 1 John 1:1. (See: rc://en/ta/man/jit/figs-abstractnouns)

death

This refers to eternal death, that is, eternity spent away from God's presence.