Peshat and Midrash Halakha

The changing understanding of “an eye for an eye” can be explained as follows: during the biblical period there was no compunction about severing limbs as a form of corporal punishment, and hence it is possible that "an eye for an eye" was indeed followed literally at that time. However, as the generations progressed, it seems that in light of moral norms it was no longer possible to arrive at a practical ruling that someone who had maimed his fellow had to have his own limb removed, and for this reason the Sanhedrin used its authority to interpret the verses in a different way, with the faith that this was God's will and that the Torah had permitted this change from the outset.