21 Thou shalt neither vex a stranger, nor oppress him: for ye were strangers in the land of Egypt.

The next several verses speak against harming those who are most vulnerable and indefensible. Today’s verse in particular focuses on the stranger, or foreigner, who lived among the Israelites. Someone who was a part of the population, even if they were not themselves Hebrew. And though this person had chosen not to follow the doctrine of the Lord, still that person was put under the Lord’s protection. God required that such a person be not vexed or oppressed, the reason given was because the Israelites were also a strange people in Egypt, and Egypt did oppress and vex them.

This is an early indication of the flip side of an eye-for-an-eye, which is the golden rule that would later be taught by Jesus, “do unto others as you would have others do unto you.” Because Israel would like to have been treated fairly while in a strange land, they should also treat their own strangers fairly also.

The logic of the golden rule is completely sound. Indeed, the best metric to consider the fairness and justice of any social policy is, “would this behavior destroy its own advocates if wielded by all other parties?” If one party has a principle that allows them to denigrate and destroy others, then that same party would also be denigrated and destroyed by other parties holding the same principle. Thus, the principle is self-defeating. A party that holds a principle of respecting the liberty of strangers, on the other hand, would see that same party having their liberty respected by all strangers who shared the same principle. It is therefore self-affirming. Thus, only the policies that meet the metric of “do unto others as you would have others do unto you” are logical.