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Under the Law the Jews were allowed to give 40 strokes only, when giving a beating as a punishment.
Deuteronomy 25:3 Forty stripes he may give him, and not exceed: lest, if he should exceed, and beat him above these with many stripes, then thy brother should seem vile unto thee.
The Jews, possibly to obviate a mistake in counting, restricted a beating to 39 stokes.Paul says he was beaten with 39 strokes 5 times by the Jews.
2 Corinthians 11:24 Of the Jews five times received I forty stripes save one.
There is only one record of Peter being beaten by the Jews that I am aware of.
Acts 5:40 And to him they agreed: and when they had called the apostles, and beaten them, they commanded that they should not speak in the name of Jesus, and let them go.
It is likely that he received 39 strokes but not completely certain.
I hope this helps.