The term "brother" is from the Greek adelphos. It technically signifies "from the same womb." The word is used in different senses in the New Testament.
- It is employed literally to identify siblings of the same parents (Acts 12:2).
- It can denote those of the same nation (Acts 2:29; 9:17; 22:5). Ananias' use of "brother" concerning Saul does not imply that the persecutor was already a Christian before having his sins "washed away" (Acts 22:16).
- The most common form in the New Testament has to do with those who have shared in a common new birth process (Jn. 3:3-5) and who are, therefore, kinsman in the Lord (see Phil. 1:14; 4:1; Col. 1:2; 1 Thes. 5:27; Philem. 16). It is not appropriate to refer to those as brethren who nominally profess an identification with Christianity, but who have not genuinely obeyed the gospel of Christ (2 Thes. 1:8; 1 Pet. 4:17).