1 Corinthians 10:8

Let us stop practicing immorality, as some of them did, and on one day twenty-three thousand fell dead.

Hebrews 2:2-3

For if the message spoken through angels proved to be valid, and every violation and infraction of it had its adequate penalty,

Treasury of Scripture Knowledge

Summary

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

Bible References

There fell

1 Corinthians 10:8
Let us stop practicing immorality, as some of them did, and on one day twenty-three thousand fell dead.
Hebrews 2:2
For if the message spoken through angels proved to be valid, and every violation and infraction of it had its adequate penalty,