Exodus 32:28-30

Darby Translation

²⁸ And the sons of Levi did according to the word of Moses; and there fell of the people that day about three thousand men.

²⁹ And Moses said, Consecrate yourselves to-day to Jehovah, yea, every man with his son, and with his brother, and bring on yourselves a blessing to-day.

³⁰ And it came to pass the next day, that Moses said to the people, Ye have sinned a great sin. And now I will go up to Jehovah: perhaps I shall make atonement for your sin.