Sabef lived during the reign of Horus Qa'a, at the end of the 1st Dynasty. He was “Governor of the Residence” and “Keeper of the secrets and decrees”, which shows that he held a high position of confidence in the royal administration, and was a priest. He was also overseer of the Heb-Sed and “Keeper of the tomb" of Qa'a.
Sabef is known from a stela found in the tomb of Qa'a at Umm el-Qa'ab, in the chambers that would normally constitute the subsidiary graves of Qa'a's tomb. It is the oldest known stela where a high functionary is actually represented.
The fact that his stela was found in a subsidiary tomb, which is part of Qa'a's tomb, would imply that Sabef was buried at the latest at the same time as Qa'a. This is seen as evidence of retainer sacrifice at the end of the 1st Dynasty, be it that it is very surprising that such a practice would apply to such a highly placed official as Sabef. A less dramatic interpretation would be that Sabef had a votive stela placed in the tomb of his king, hoping he would thus be able to participate in the king’s afterlife.