He left the car running the whole time.
40-year-old William Moultrie, of Newark, is under arrest. Police say he locked the infant in the car outside the Sears along Eagle Run Road in Newark around 6:30 Saturday night.
The baby was reportedly in there for nearly half an hour.
Police say Moultrie told them he thought it would only take 5 minutes to return the gift.
Moultrie is charged with Endangering the Welfare of a Child.
The Division of Family Services was contacted and the child was turned over to a relative.