anastrephō

Behind this word is an ordinary physical picture: moving about, turning this way and that, going in and out among people in a particular place. Long before the New Testament, Greek writers had stretched that picture into a way of talking about life itself, so that to move about among people came to mean to live among them in a certain way. By the time of the New Testament this was a standard way to say what kind of person someone actually was in practice.

Because the picture is a social one, the word almost always says where, or among whom, or in what manner the living happens. The New Testament writers fill in that blank in strikingly different ways:

• in the world, with pure motives and by the kindness of God, as Paul defends how he and his coworkers had acted
• in the household of God, which is the church, in the instruction left for Timothy
• in the cravings of the body, describing the life the readers had been rescued from
• in error, describing the teachers who lure unsteady believers back
• honorably, and in reverent awe, as a plain command covering the whole of a believer's life

The matching noun from the same root (ἀναστροφή) names the finished pattern such living produces, a person's whole way of life as others can see it. This verb names the living itself, in progress, and it keeps a use the noun does not: it can also describe someone on the receiving end, being put through a certain kind of treatment.

Set beside the far more common picture for the moral life, περιπατέω, "to walk," which keeps the image of a road with a direction and steps taken in it, this word pictures a person moving among others and carrying themselves a certain way in their company. That is why it fits so naturally in a command about how to behave inside a household.

This is the word's plainer, more physical use. It shows up twice: temple officers go back from the jail to report that the prisoners are gone, and, in a promise of God quoted at the meeting in Jerusalem, God says that after these things he will come back and rebuild what has collapsed.

The same physical turning lies underneath the word's much commoner use for how a person lives, so it is the surrounding sentence, not the word on its own, that tells a reader which is meant. Greek had a more ordinary word for going back, ὑποστρέφω, which means only that and never says anything about how someone behaves. That is worth remembering in reverse too: when this word appears, a reader should not assume it must mean physical return.