en_tn_lite_do_not_use/heb/03/12.md

brothers

Here this refers to fellow Christians, including males and females. Alternate translation: "brothers and sisters" or "fellow believers" (See: rc://en/ta/man/jit/figs-metaphor and rc://en/ta/man/jit/figs-gendernotations)

that none of you has an evil heart of unbelief, a heart that turns away from the living God

Here "heart" is a metonym that represents a person's mind or will. Refusing to believe and obey God is spoken of as if the heart did not believe and it physically turned away from God. Alternate translation: "that none of you refuses to believe the truth and stops obeying the living God" (See: rc://en/ta/man/jit/figs-metonymy and rc://en/ta/man/jit/figs-metaphor)

the living God

"the true God who is really alive"