'Brethren' in the Bible

If thou put the brethren in mind of these things, thou shalt be a good minister of Christ Jesus, nourished in the words of the faith, and of the good doctrine which thou hast followed until now :

Rebuke not an elder, but exhort him as a father; the younger men as brethren:

And they that have believing masters, let them not despise them, because they are brethren; but let them serve them the rather, because they that partake of the benefit are believing and beloved. These things teach and exhort.