Yahweh calls on the heavens to drop and the clouds to pour out the rain of righteousness. Justice drops from heaven, just like mercy (ask Portia!). The result is that the earth produces the fruit of salvation and justice (Isaiah 45:8).
In a drought, nothing springs up from the earth; there’s no fruit. The fruit of justice depends on what comes down from the sky, the rain of the Spirit. And it depends on the earth’s receptiveness of that heavenly rain.
Earthly justice is as dependent on gifts from heaven as plants are dependent on rain.