Literally to walk around, but Paul uses it pervasively as a metaphor for how one lives and conducts oneself — 'walking in the Spirit,' 'walking in love,' 'walking in the light.' Life as a sustained direction of travel.
The Pauline 'walk' ethic is dynamic, not static — life is movement, direction, pace. To walk 'worthy' of the gospel means moving in a way consistent with what God has done. Seven 'walks' in Ephesians structure its ethics.
Ephesians alone has seven peripateo calls (2:2, 2:10, 4:1, 4:17, 5:2, 5:8, 5:15). Each describes a dimension of the new life: worthy, in love, in light, in wisdom. The Christian life is a sustained purposeful walk.