What is the meaning of verse 189 from Surah Al Imran, "Indeed, in the creation of the heavens and the earth and the alternation of the night and the day are signs for those of understanding," and who are "those of understanding" (ūlū al-albāb)?

The Almighty says: ﴿Indeed, in the creation of the heavens and the earth and the alternation of the night and the day are signs for those of understanding Who remember Allah while standing or sitting or [lying] on their sides and ponder upon the creation of the heavens and the earth﴾ [Al Imran: 190-191].

This verse means that in the creation of the heavens and the earth, and the magnificent signs within them, and in the succession of night and day in terms of length and shortness, there are clear proofs of the Creator's greatness and power for those with complete and intelligent minds. These individuals remember Allah in all their states and ponder upon the creation of the heavens and the earth, thus understanding the wisdom within them that indicates the Creator's greatness, power, knowledge, wisdom, and mercy.