In the Old Testament, the books of Exodus, Leviticus and Deuteronomy make similar statements about the treatment of strangers. For example, Exodus 22:21 says: "Thou shalt neither vex a stranger, nor oppress him: for ye were strangers in the land of Egypt". These texts are frequently used in sermons to plead for compassion and tolerance of those who are different from us and less powerful. Julia Kristeva elucidated a philosophy of political and religious toleration based on all of our mutual identities as strangers.