'Brother' in the Bible

Paul, an apostle (special messenger, personally chosen representative) of Christ Jesus (the Messiah, the Anointed) by the will of God, and Timothy our brother,

As to all my affairs, Tychicus, who is a much-loved brother and faithful assistant and fellow bond-servant in the Lord, will give you all the information.

and with him is Onesimus, our faithful and beloved brother, who is one of you. They will let you know everything about the situation here [in Rome].