When John Cotton's grandson, Cotton Mather, wrote his Ecclesiastical History of New England in 1702, he told a story about [John] Winthrop that I would like to believe is true. In the middle of winter, Boston was low on fuel and a man came to the governor complaining that a "needy person" was stealing from his woodpile. Winthrop mustered the appropriate outrage and requested that the thief come see him, presumably for punishment. According to Mather, Winthrop tells the man,I loved that. And it was fresh on my mind when my daily reading found me at Proverbs 22:8: "Whoever sows injustice will reap calamity, and the rod of his fury will fail.""Friend, it is a severe winter, and I doubt you are but meanly provided for wood; wherefore I would have you supply yourself at my woodpile till this cold season be over." And Winthrop then merrily asked his friends whether he had not effectually cured this man of stealing his wood.
I think the reverse can be true as well. "Doing unto others" is most certainly a way to sow justice. Winthrop here did not fail the measure of justice. Perhaps the thief deserved punishment, but Winthrop put a stop to his thievery by freely giving from himself what the thief was taking from another. In doing so, he doesn't just put a stop to the thievery but he puts a stop to the need.
Isn't this what God has done for us in Christ on the cross? He satisfies his desire for justice and simultaneously satisfies our need. That he does it in an unexpected way, offering the Treasure of his own storehouse, is part of the power of the gospel that bears fruit and grows. Let us enact living parables of Christ's kingdom and Christ as King -- which is what I think Winthrop did there -- let us sow this justice, for whoever does so will reap a eucatastrophe.