'Brethren' in the Bible

These things placing before the brethren, thou shalt be a good ministrant of Jesus Christ, being nourished by the words of the faith, and of the good teaching, which thou didst follow after,

An aged person thou mayest not rebuke, but be entreating as a father; younger persons as brethren;

and those having believing masters, let them not slight them, because they are brethren, but rather let them serve, because they are stedfast and beloved, who of the benefit are partaking. These things be teaching and exhorting;