'Brother' in the Bible

Paul, a prisoner of Christ Jesus, and Timothy our brother, to Philemon our beloved and fellow-worker,

For I had much joy and comfort in thy love, because the hearts of the saints have been refreshed through thee, brother.

no longer as a servant, but more than a servant, a brother beloved, specially to me, but how much rather to thee, both in the flesh and in the Lord.

Yea, brother, let me have joy of thee in the Lord: refresh my heart in Christ.