Exodus 30:11 KJV
And the Lord spake unto Moses, saying,
Exodus 30:11, King James Version
In context
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,
12 When thou takest the sum of the children of Israel after their number, then shall they give every man a ransom for his soul unto the Lord, when thou numberest them; that there be no plague among them, when thou numberest them.