It is an old ritual in which one symbolizes himself as being scarified to God or a sign of submission to God also known as ‘Nazar kai phairay‘. Same is the rationale for 7 rounds of ‘sae’ of ‘safa and marwa’, they are also ‘nazar kai phairay‘. The former represents sacrificial rounds around the place of worship (‘Mabad kai Phairay‘) and the latter represents the sacrificial rounds around the altar (‘Qurbangah kai phairay‘)

Please also refer to the link below from 5:36 to 11:04

ilm-o-Hikmat 07-06-2020