In The Name of Allaah, The Most Merciful, The Bestower of Mercy
Allaah (The Most High) said:
وَٱلضُّحَىٰ (١) وَٱلَّيۡلِ إِذَا سَجَىٰ (٢) مَا وَدَّعَكَ رَبُّكَ وَمَا قَلَىٰ (٣) وَلَلۡأَخِرَةُ خَيۡرٌ۬ لَّكَ مِنَ ٱلۡأُولَىٰ (٤)
وَلَسَوۡفَ يُعۡطِيكَ رَبُّكَ فَتَرۡضَىٰٓ (٥) أَلَمۡ يَجِدۡكَ يَتِيمً۬ا فَـَٔاوَىٰ (٦) وَوَجَدَكَ ضَآلاًّ۬ فَهَدَىٰ (٧) وَوَجَدَكَ
عَآٮِٕلاً۬ فَأَغۡنَىٰ (٨) فَأَمَّا ٱلۡيَتِيمَ فَلَا تَقۡهَرۡ (٩) وَأَمَّا ٱلسَّآٮِٕلَ فَلَا تَنۡہَرۡ (١٠) وَأَمَّا بِنِعۡمَةِ رَبِّكَ فَحَدِّثۡ
By the forenoon (after sun-rise); and by the night when it is still (or darkens); Your Lord (O Muhammad) has neither forsaken you nor hated you. And indeed the Hereafter is better for you than the present (life of this world). And verily, your Lord will give you (all i.e. good) so that you shall be well-pleased. Did He not find you (O Muhammad) an orphan and gave you a refuge? And He found you unaware (of the Qur’an, its legal laws, and Prophet hood, etc.) and guided you? And He found you poor, and made you rich (self-sufficient with self-contentment, etc.)? Therefore, treat not the orphan with oppression, and repulse not the beggar; and proclaim the Grace of your Lord (i.e. the Prophet -hood and all other Graces). [Surah Ad-Duhaa]
Allaah (Glorified Be He and Free is He From all Imperfections) swore by two of His great creations – the Night and the Day- both of which are an indication of His Perfect and Absolute Lordship, Perfect Wisdom and Perfect Mercy. Allaah is the one (alone) Who dispels the night by way of the Daylight and likewise He is the one Who dispels the darkness of ignorance and Shirk by way of the revelation and Prophet-hood.
Likewise due to His Mercy, it necessitates that His slaves are not left in the darkness of night permanently, rather He guides them towards the beneficial affairs of the worldly life and their livelihoods by way of the Daylight, therefore it does not befit His (Majesty) that He leaves them in the darkness of ignorance and deviation; rather He guides them by way of the light of revelation and Prophet-hood in order that they may attain well-being in this life and the next.
[Source: Badaa’i At-Tafseer Al-Jaami Limaa Fassarahu Al-Imaam Ibnul Qayyim Al-Jawziyyah’ Vol 3’ page 327. Abridged and paraphrased]