The term “judgment” (krisis, Greek) means more than a verdict. Its meaning includes a trial with a decision that can go either way—as in a crisis (English). Although “day” can signify twenty-four hours, it often has a wider meaning—such as Noah's Day, Washington's day, or “the day of temptation in the wilderness,” which was forty years (Hebrews 3:8,9).
The Apostle Peter identifies the “day of judgment” as “a thousand years” (2 Peter 3:7, 8). It is the Millennial “day of Christ” in which Christ will reign, and “judge the world in righteousness.” During that age of judgment, the world will be granted a trial for life as well as a verdict (Philippians 2:16; Acts 17:31).
“When thy judgments are in the earth, the inhabitants of the world will learn righteousness” (Isaiah 26:9).
When we consider all the work to be accomplished for earth's billions, this wider meaning of “day” is most logical.