lex talionis

is not in fact about physical retaliation... it is written in this extreme way in order to drive home the point that the aggressor should not simply pay his victim off and be done with it, but that he must truly contemplate the profound damage to the quality of life of his fellow, and that he should himself endure profound suffering to the same extent for the rest of his life before God.

The answer offered by Maimonides and Maharal (16th century Prague) is based upon a profound sense of responsibility for one's actions. The Torah, by expressing the payment in this way, is teaching an important and crucial lesson. Had the Torah simply ordered the aggressor to pay damages, he might have thought that it is sufficient to simply write a check to the victim and he is done. . . . The Torah is teaching that if one perpetrates a loss of limb to his fellow, he truly deserves to have the same done to his self. He should truly contemplate the profound damage to the quality of life of his fellow, his pain and suffering he is forced to endure for the rest of his life. He has done a terrible thing and the slate will not be cleared by monetary payment alone. He must beg forgiveness from the injured party for what he has done, and perform Teshuva, repentance to God, coupled with making serious life changes that will ensure a similar act will not be repeated. Rabbi Yerachmiel Fried

lex talionis, n.Definitions

lex talionis