The Christian Bible (Matthew 15:11f) describes a dialogue between Jesus and his disciples. Jesus maintains that: “a man is not defiled by what enters his mouth, but by what comes out of it.” His disciples caution that this teaching would run afoul of the Pharisees who, following the Torah (Leviticus 11), uphold the view that eating certain creatures is forbidden. But Jesus refuses to yield and insists that a person’s diet is less a matter of concern to God than a person’s speech and actions.
How the rabbis actually reacted to Jesus’ teaching is unknown. But we can imagine the rabbis saying something like this. What comes out of a person’s mouth is indeed important. That is why the Torah forbids cursing a parent (Leviticus 20:9), blasphemy (Leviticus 24:16), slander (Deuteronomy 22:19), giving a false report (Exodus 23:1), and telling lies (Exodus 23:7). But what goes into a person’s mouth is important as well. Limiting one’s diet to a select number of creatures is a demonstration of concern for life. Recognizing that all animals are not available for humans to eat is a first step in weaning people away from eating fellow creatures and towards gaining deeper reverence for animal life. We are how we eat. And if we eat by taking a life we become inure to killing. That is to the detriment of civilization. Eating certain animals is a concession God makes to human desire in anticipation of a time when human beings will be better able to control their appetites.
Moreover, as fifteenth century Spanish Rabbi Isaac ben Moses Arama points out in his commentary entitled Akedat Yitzhak, no poisonous plants or animals are listed as permitted. From this we learn that we are what we eat. The aspiration to become better, nobler, nicer people would be thwarted if we consumed noxious, toxic food. No wonder, then, that the Torah (Deuteronomy 30:14) tells us that awareness of God’s design for us is “in our mouths and in our hearts.”
We need not choose between what comes out of our mouths and what goes into our mouths. Both are of concern.