'Brethren' in the Bible

Both Jesus who sanctifies and those who are sanctified [that is, spiritually transformed, made holy, and set apart for God’s purpose] are all from one Father; for this reason He is not ashamed to call them brothers and sisters,

saying,“I will declare Your (the Father’s) name to My brethren (believers),In the midst of the congregation I will sing Your praise.”

Therefore, it was essential that He had to be made like His brothers (mankind) in every respect, so that He might [by experience] become a merciful and faithful High Priest in things related to God, to make atonement (propitiation) for the people’s sins [thereby wiping away the sin, satisfying divine justice, and providing a way of reconciliation between God and mankind].

Therefore, holy brothers and sisters, who share in the heavenly calling, [thoughtfully and attentively] consider the Apostle and High Priest whom we confessed [as ours when we accepted Him as Savior], namely, Jesus;

Take care, brothers and sisters, that there not be in any one of you a wicked, unbelieving heart [which refuses to trust and rely on the Lord, a heart] that turns away from the living God.

It is true that those descendants of Levi who are charged with the priestly office are commanded in the Law to collect tithes from the people—which means, from their kinsmen—though these have descended from Abraham.

Therefore, believers, since we have confidence and full freedom to enter the Holy Place [the place where God dwells] by [means of] the blood of Jesus,

I call on you, brothers and sisters, listen [patiently] to this message of exhortation and encouragement, for I have written to you briefly.