Isaiah 5:4 (BSB)

What more could have been done for My vineyard than I have done for it? Why, when I expected sweet grapes, did it bring forth sour fruit?

From Isaiah 5. Also in the ESV.

Commentary on Isaiah 5:4

• John Calvin (Reformed), Calvin's Commentaries on Isaiah 5:4: 4. What more ought to have been done to my vineyard? He first inquires what could have been expected from the best husbandman or householder, which he has not done to his vineyard? Hence he concludes that they had no excuse for having basely withheld from him the fruit of his toil. How did I expect that it would yield grapes?
• Matthew Henry (Presbyterian), Matthew Henry's Complete Commentary on Isaiah 5:1-7: See what variety of methods the great God takes to awaken sinners to repentance by convincing them of sin, and showing them their misery and danger by reason of it. To this purport he speaks sometimes in plain terms and sometimes in parables, sometimes in prose and sometimes in verse, as here.
• John Gill (Reformed Baptist), Exposition of the Old and New Testaments on Isaiah 5:4: What could have been done more to my vineyard, that I have not done in it?.... Or "ought", as the Vulgate Latin: this is generally understood of good things done to it in time past; as what better culture could it have had? what greater privileges, blessings, and advantages, natural, civil, and religious, could have been bestowed on this people?
• Jamieson-Fausset-Brown (Reformed), Commentary Critical and Explanatory on the Whole Bible on Isaiah 5:4: God has done all that could be done for the salvation of sinners, consistently with His justice and goodness. The God of nature is, as it were, amazed at the unnatural fruit of so well-cared a vineyard.