The 300th prohibition is that a judge is forbidden [to order] to lash a transgressor so severely as to threaten his physical integrity. The explanation of this is as follows: one who is to be punished by lashing receives a maximum of 40 lashes [i.e. 39,] as explained in the Oral Tradition.1 But a person is never given lashes before his tolerance is determined in accordance with his age, condition, and size. If he will be able to survive the full number of lashes, they are all administered. If he will not survive the full number, he is given as many lashes as [it is estimated that] he is able to take — with a minimum of three. This is learned from G‑d's statement, (exalted be He),2 "[have him flogged] according to his wickedness." The maximum number of lashes is 39,3 and this prohibition comes to forbid even one extra lash above the number determined by the judge.
The source of this prohibition is G‑d's statement4 (exalted be He), "[Have him flogged] according to his wickedness. Do not go beyond the limit and give him forty lashes."
The Sifri5 says, "If one adds on to the number of lashes, one transgresses a prohibition. This teaches the prohibition only for one who adds on to the 40 lashes. What is the source of the prohibition for one who adds on the estimation of the High Court? From the phrase, 'Do not go beyond the limit.' "
This prohibition also forbids one to strike any Jew:6 If it is prohibited even to strike a transgressor [even one extra time] how much moreso for striking another person! Our Sages also prohibited one from threatening to hit another, even without actually doing so. They said,7 "Anyone who lifts his hand against another to strike him is called wicked, as it is written,8 'And he said to the wicked one, Why did you hit your neighbor?' "
