The Might and Power of Allah Allah tells us that He

يُولِجُ الَّيْلَ فِى النَّهَارِ

(merges the night into the day,) meaning, He takes from the night and adds to the day, so that the day becomes longer and the night shorter, which is what happens in summer when the days are longest; then the day starts to become shorter and the night longer, which is what happens in winter.

This has been stated in the verse: وَلَوْ أَنَّمَا فِي الْأَرْ‌ضِ مِن شَجَرَ‌ةٍ أَقْلَامٌ (27) through a similitude. Says the similitude: 'If all trees that are on the earth were to be pens (or pens were to be made of all branches on them) and the ocean (converted into ink) is supported by seven seas following it, the words of Allah would (still) not come to an end.' The expression: کلمات اللہ (kalimatul-lah, i.e. the words of Allah) means His knowledge and wisdom (Ruh ul-Maani and Mazhari) which includes the manifestations of Divine power and Divine blessings. Then, the 'seven seas', referred to here, do not mean that there are seven seas present elsewhere. Instead of that, this is a manner of saying: Suppose if this ocean were to be replenished with seven more oceans, still then, all these words of Allah could not be committed to writing. Even the number of 'seven' appears here as a part of the example. No restriction is intended. Another verse of the Qur'an proves it. There it was said:

قُل لَّوْ كَانَ الْبَحْرُ‌ مِدَادًا لِّكَلِمَاتِ رَ‌بِّي لَنَفِدَ الْبَحْرُ‌ قَبْلَ أَن تَنفَدَ كَلِمَاتُ رَ‌بِّي وَلَوْ جِئْنَا بِمِثْلِهِ مَدَدًا