As a story, the tension is built by having the Lord of the vineyard ready to cut down all trees and cast them into the fire. The servant prevails upon the Lord of the vineyard to be yet patient, and the Lord acquiesces.
As with the comment on Jacob 5:25–28, the picture of a God wanting to destroy who is being held off by his servant is part of the story, but not a reflection of the reality of God. It is God who has planted the vineyard and who desires it to thrive, and who ultimately does all that is possible to save humankind.