send someone about his or her business
Also, send someone packing. Dismiss someone abruptly, as in They always ring the bell at suppertime, asking for signatures, but I send them about their business, or The owner caught Jack taking small items from the store and sent him packing. The first term, which in effect tells people to tend to their own affairs, was first recorded in 1768; the variant, alluding to telling people to pack their bags and leave, was first recorded in 1594. Also see send away.