وَالضُّحَىٰ وَاللَّيْلِ إِذَا سَجَىٰ
By the morning brightness, and by the night when it becomes still.
Ad-Duḥā 93:1–2 evokes brightness and the stillness of night; 93:3 denies abandonment by the Lord. The oaths focus attention and create a dignified opening before the reassuring assertion.
The juxtaposition of day and night and their position before the assertion are observable. A detailed one-to-one symbolism for every element, however, would need evidence beyond the wording.