Forty times he shall strike him; he shall not add, lest he continue to strike him beyond these with a great blow, and your brother be degraded before your eyes.
English: ‘He shall not add, lest he add’ – why is this needed? Because one exhorts only those who are already diligent.
On the daf / in context: The double language of warning is explained as reinforcement directed at the conscientious officer who might still be tempted to continue.
Type of Learning
Derash on doubled language of caution (Bavli).
What Is Learned
Even a carefully chosen officer requires explicit warning not to exceed the number; the Torah doubles the caution because only the already-careful respond to exhortation.