What is the ruling on the saying: "Thus have the days decreed among their people," and do the days decree?

The poet Al-Mutanabbi coined the phrase "Thus have the days decreed" to describe the state of Sayf al-Dawla, victorious over the Byzantines. By this, he meant that what occurred in the world pleased some people and displeased others. Linguists call this "metonymy" (al-majāz al-ʿaqlī), which is attributing an action, or what is similar to it, to something other than what it truly belongs to. There is no religious impediment to this, and it has many proofs in the Quran and Sunnah. The Holy Quran attributes the graying of children's hair to the Day of Judgment, even though the true cause of graying is Allah. It also attributes encompassing to the Day, even though what truly encompasses is Allah's punishment.