Deuteronomy 17:6

6 On the testimony of two or three witnesses a person is to be put to death, but no one is to be put to death on the testimony of only one witness.

Read Deuteronomy 17:6 Using Other Translations

At the mouth of two witnesses, or three witnesses, shall he that is worthy of death be put to death; but at the mouth of one witness he shall not be put to death.
On the evidence of two witnesses or of three witnesses the one who is to die shall be put to death; a person shall not be put to death on the evidence of one witness.
But never put a person to death on the testimony of only one witness. There must always be two or three witnesses.

What does Deuteronomy 17:6 mean?

John Gill's Exposition of the Bible
Deuteronomy 17:6

At the mouth of two witnesses, or three witnesses, shall he
that is worthy of death be put to death
The idolater found guilty was to be stoned; two witnesses were sufficient to prove a fact, if three the better, but, on the testimony of one, sentence might not be pronounced. Aben Ezra observes, that some say, if two witnesses contradict two other, a third turns the scale and determines the matter; and others say, that two who are wise men will do, and three of others; and because it is said "at the mouth" of these witnesses, it is concluded, that a testimony should be verbal and not written; should not be recorded, neither in pecuniary cases nor in capital ones, but from the mouth of the witnesses, as it is said "at the mouth" at their mouth, and not from their handwriting F5:

[but] at the mouth of one witness he shall not be put to death;
so careful is the Lord of the lives of men, that none should be taken away but upon full and sufficient evidence, even in cases in which his own glory and honour is so much concerned.


FOOTNOTES:

F5 Maimon. Hilchot Eduth, c. 3. sect. 4.
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