en_tn/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)

there will not be anyone with 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: "there will not be any of you who refuse to believe the truth and who stop 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"