This commentary explains ayahs 40:66–68 together.
The Prohibition of Shirk, the Order for Tawhid, and the Evidence
Allah says, `say, O Muhammad, to these idolators, that Allah forbids them to worship anyone, such as these idols and false gods, except Him.' Allah explains that no one apart from Him is deserving of worship, as He says:
هُوَ الَّذِى خَلَقَكُمْ مِّن تُرَابٍ ثُمَّ مِن نُّطْفَةٍ ثُمَّ مِنْ عَلَقَةٍ ثُمَّ يُخْرِجُكُمْ طِفْلاً ثُمَّ لِتَـبْلُغُواْ أَشُدَّكُـمْ ثُمَّ لِتَكُـونُواْ شُيُوخاً
(It is He, Who has created you from dust, then from a Nutfah then from a clot (a piece of coagulated blood), then brings you forth as an infant, then (makes you grow) to reach the age of full strength, and afterwards to be old.) meaning, He is the One Who Alone, with no partner or associate, causes you to pass through these different stages, and this happens in accordance with His command, will and decree.
وَمِنكُمْ مَّن يُتَوَفَّى مِن قَبْلُ
(though some among you die before) means, before being fully formed and emerging to this world; so his mother miscarries him. And there are some who die in infancy or in their youth, or when they are adults but before they reach old age, as Allah says:
لِّنُبَيِّنَ لَكُمْ وَنُقِرُّ فِى الاٌّرْحَامِ مَا نَشَآءُ إِلَى أَجَلٍ مُّسَمًّى
(that We may make (it) clear to you. And We cause whom We will to remain in the wombs for an appointed term) (22:5).
وَلِتَبْلُغُواْ أَجَلاً مُّسَمًّى وَلَعَلَّـكُمْ تَعْقِلُونَ
(and that you reach an appointed term in order that you may understand. ) Ibn Jurayj said, "In order that you may remember the Resurrection." Then Allah says:
هُوَ الَّذِى يُحْىِ وَيُمِيتُ
(It is He Who gives life and causes death.) meaning, He is the Only One Who does that, and none is able to do that except He.
فَإِذَا قَضَى أَمْراً فَإِنَّمَا يَقُولُ لَهُ كُن فيَكُونُ
(And when He decides upon a thing He says to it only: "Be!" -- and it is.) means, He cannot be opposed or resisted. Whatever He wills definitely comes to pass.