Exodus 30:10 in the World English Bible
Aaron shall make atonement on its horns once in the year; with the blood of the sin offering of atonement once in the year he shall make atonement for it throughout your generations. It is most holy to the LORD.”
Context
9 Ye shall offer no strange incense thereon, nor burnt sacrifice, nor meat offering; neither shall ye pour drink offering thereon.
10 And Aaron shall make an atonement upon the horns of it once in a year with the blood of the sin offering of atonements: once in the year shall he make atonement upon it throughout your generations: it is most holy unto the LORD.
11 And the LORD spake unto Moses, saying,