'Useful' in the Bible

Look! It is given to the fire as fuel. The fire will consume two of its ends, and its middle will be charred. Is it useful for anything?

Therefore, if someone cleanses himself from these [things], he will be a vessel for honorable use, set apart, useful to the Master, prepared for every good work.

Luke alone is with me. Take along Mark [and] bring [him] with you, because he is useful to me for ministry.

Once he [was] useless to you, but now [he is] useful to you and to me,