Isaiah 45:8. “Drop down, ye heavens, from above, and let the skies pour down righteousness: let the earth open, and let them bring forth salvation, and let righteousness spring up together; I the Lord have created it.”
This is a poetic, lyrical verse that looks to the far future when Messiah rules from Jerusalem. I’ve looked at several commentaries, but this one from Pulpit Commentary iis the one that appealed the most to me:
THE BLESSED RESULTS OF ISRAEL’S DELIVERANCE. The restoration of Israel to their own land will be followed by a great increase of righteousness and salvation. They will be, as it were, showered down abundantly from heaven, while at the same time they will spring in profusion from earth’s bosom. Jehovah, who has caused the deliverance, will also cause these results to follow from it. Verse 8. – Drop down, ye heavens; literally, distil, ye heavens (camp. Deuteronomy 32:1; Job 36:28); or rain down on the thirsty earth your gracious influences. Let righteousness, or God’s law of right, descend afresh from the skies as a boon to mankind – a boon for which they have been long waiting. And… let the earth open. Let earth make due response, opening her gentle besom, as she does in spring (camp. Aprilis from aperio), and blossoming with human righteousness, the fruit and evidence of salvation. To the prophet’s rapt gaze the excellence of the post-Captivity times, when all idolatry had been put away, seemed, in comparison with earlier ages, the reign of justice and truth upon earth. I the Lord have created it; i.e. “I, Jehovah, have wrought the change by the larger outpouring of my Spirit” (camp. Isaiah 43:3).
I often refer to the website Biblehub.com when I’m looking for good commentary. They give you a wide variety of writers, clarifying the scriptures. You can also find the passage in a wide variety of versions and translations, which is also a helpful feature. It’s a good tool. If you’ve never been there, you should look at it.