I was taught that the reason they gave 40 stripes save 1 was because if the person who was meting out the stripes miscounted and gave more than 40, it would dishonor his brother.
Deuteronomy 25:
1 If there be a controversy between men, and they come unto judgment, that the judges may judge them; then they shall justify the righteous, and condemn the wicked.
2 And it shall be, if the wicked man be worthy to be beaten, that the judge shall cause him to lie down, and to be beaten before his face, according to his fault, by a certain number.
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.
vs 2 – the judge determined the number "according to his fault" ... and the judgment would be meted out before the judge.
vs 3 – 40 stripes was the maximum penalty ... and if 40 was exceeded, that would dishonor the one at fault.
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