I read something long ago that discussed how we often describe the future as something ahead, and the past as something left behind, contrasting it with how we can see (remember) the past while the future is unknown, so it's more like we're facing the past with our backs to the future. I found that an interesting observation of a language contradiction, and the 'moving back' as in to the future seems to fit in that.
it also reminded me of something else I read, about languages that didn't have relative directions (right, left, ahead, back), only absolute ones (north, south, east, west), whose native speakers got very nervous if they got disoriented. in one variant of that language, passage of time was also strongly associated with the west/east direction, so arranging pictures so as to form a story just had to be done east to west. so cool