Deuteronomy 17:4-6

New Revised Standard Version, Anglicised Catholic Edition

⁴ and if it is reported to you or you hear of it, and you make a thorough inquiry, and the charge is proved true that such an abhorrent thing has occurred in Israel, ⁵ then you shall bring out to your gates that man or that woman who has committed this crime and you shall stone the man or woman to death. ⁶ On the evidence of two or three witnesses the death sentence shall be executed; a person must not be put to death on the evidence of only one witness.