Your Jewish friend is not alone in the notion of “no justice, no peace.” And he has a point. Peace in and of itself can simply perpetuate the exploitation of the powerless. Justice is the higher value, and will in time lead to peace. But I doubt that is what your friend was talking about. He doesn’t want justice; he wants revenge.
The primary justice issue for Jews today has to do with Israel and her treatment of her Arab citizens and Palestinian neighbors. Many Jews want to blame the Palestinians for all the ills of the region, but any objective observer knows that both sides act wickedly. Mercy might be the more strategic choice, allowing Palestinian anger and fear of Israelis (and Israeli anger and fear of Palestinians) to cool. Then they might be able to work together for justice. There are hundreds of peace groups in Israel involving Israelis and Palestinians, and all of them take compassion and mercy as the first step to justice and peace.
In the Kabbalah (Jewish mysticism) the Tree of Life is considered the map of the universe that reveals the spiritual DNA of every part and particle of both Creation and its Creator. Justice (called Gevurah or Din in Hebrew) is paired with Chesed (mercy). The idea is that each balances the other. Too much din in the world and you have a police state; too much chesed and you have anarchy. Too much din in God and you have a dead world lacking all creativity and the mutations necessary for evolution. Too much chesed and you have a dead world lacking all law and structure. There is no ideal balance but a dynamic harmony between the two (both in God and the world) must be sought in each case. It is up to the people involved to determine what that dynamic harmony is.
The real challenge I see in this Beatitude is to define what we mean, or what Jesus may have meant, by “mercy”. I would define mercy behaviorally: “That which is hateful to you, do not do to others,” to quote Rabbi Hillel (Talmud, Shabbat 31a); or, in Jesus’ formulation, “Do unto others as you would have others do unto you” (Matthew 7:12). Every religion teaches this ethics of reciprocity, and because it is so clearly reciprocal it may well be the idea behind this Beatitude: be merciful and you will receive mercy.
With this definition in mind we can take up the questions you raise. Should Jews in Jesus’ day act mercifully toward their Roman occupiers? Yes, for that is the only way to effect change. Should the Priest and Levite violate their legal obligations to avoid dead bodies, and looked to see if the person they passed on the road was actually dead? Of course, isn’t that what they would want of others if they themselves had been mugged and left dying on the roadside?
The Parable of the Two Sons (Matthew 21:28-32), however, seems to be a different kind of story. First, there is no reason to assume as you do that the father was “loving.” Jesus only says “a man had two sons.” Second, there is the assumption that doing the will of the father is the right thing to do. Knowing nothing about this father I can’t say if working the vineyard was the right thing to do or not.
If, of course, the father is God, and the vineyard is the world, and working in the vineyard means feeding the hungry, clothing the naked, freeing the unjustly imprisoned, etc, then I would say it is the right thing to do, and doing it, even against one’s initial inclination is superior to not doing it. But where does mercy come into play?
At first I didn’t see it. The father isn’t merciful; we know nothing of his reaction to his son’s decisions. But Jesus is, and his mercy really struck me. Jesus clearly equates the priests with whom he is talking with the son who agrees to work the vineyard but does not actually do so. Rather than condemn these people, Jesus just says that “tax collectors and prostitutes are going into the Kingdom of God ahead of you” (Matthew 21:31). The priests won’t be denied access to the Kingdom, they just won’t be at the head of the line.
This is another stunning act of mercy that most of Jesus’ followers have yet to imagine, let alone practice.
Your application of this beatitude to our personal life was right on target. But let me highlight your reminder that Jesus was a visionary.
It isn’t that Jesus saw what the world could be like if people lived the principles he taught in the Beatitudes, it was that Jesus actually saw the Kingdom of God as a reality. To pick up and invert an earlier point, it isn’t only that we live “as if” we were in the Kingdom of God and in so doing bring the Kingdom into being; it is also the case that the Kingdom of God is here and now, and that by seeing it (being a vision-ary) one knows how to act in accordance with it.
Both ways work. Jesus embodied the former: he saw the truth and lived it. But in the Sermon on the Mount he taught the latter, knowing that not everyone has the eyes to see. Both the way of the seer and the way of the doer lead to the same reality: a just, compassionate, and peaceful world where all beings are seen as the children of God.