Musannaf Ibn Abi Shayba 9:1709

Abu Khalid narrated to us, from Malik, from Ata, from Ibn Abbas, who said: "Satan has overcome the people regarding the hours [mentioned in the verse]: 'those whom your right hands possess and those who have not reached puberty among you.' He said: 'Their families used to teach us to seek permission.' He said: 'So one of us, when he would come, would say: "Peace be upon you, may so-and-so enter?"'"