'Fellow soldier' in the Bible

In addition, the officers are to say to the troops, "Who among you is afraid and fainthearted? He may go home so that he will not make his fellow soldier's heart as fearful as his own."

But for now I have considered it necessary to send Epaphroditus to you. For he is my brother, coworker and fellow soldier, and your messenger and minister to me in my need.

to Apphia our sister, to Archippus our fellow soldier, and to the church that meets in your house.