The notion that walking backwards is unlucky was occasionally noted in the mid-19th century from the Lancashire/Yorkshire area: ‘[Lancashire] children are frequently cautioned by their parents not to walk backwards when going on an errand; it is a sure sign they will be unfortunate in their objects’ (N&Q 1s:3 (1851), 55). Similarly, getting out of bed backwards brought bad luck.
But recipes for love divinations, such as making the dumb cake, commonly require the participants to walk backwards when going to bed, perhaps to heighten the feeling of ‘otherness’ in the proceedings, or perhaps only to make things more difficult.
In black magic, to say or do something backwards symbolizes evil intent. Clear instances are a 17th-century curse with the name of the victim written backwards; and a Lincolnshire tradition that witches must renew allegiance to the Devil annually by walking backwards round a church on St Mark's Eve (Rudkin, 1936: 73). Nowadays, a common but none too serious idea is that one can raise the Devil by saying the Lord's Prayer backwards.
See also LEFTWARD MOVEMENT.
Opie and Tatem, 1989: 422.