Salaam,
Just because Shaytaan comes from Allaah, that does not mean Shaytaan cannot fight against, cannot disobey Allaah. Does Allaah not say in His Holy Qur'aan that Iblees disobeyed Him?
Let me say some important issues which if will not be kept in mind, could result in the deviation.
Allah's orders and wills fall into one of the two ff categories,
1. Takwini(تكويني).
2. Tashri'i(تشريعي).
Disobeing Allah in His Takwini orders and wills is impossible. Indeed, these orders are Existential, not Contractual. For example, one of the Takwini wills of Allah is that the water wets the non-hydrophobic places. No one and nothing can disobey this will of Allah.
Here is a Quranic example for Takwini order and will of Allah, 41:11
Then He turned to the heaven, and it was smoke, and He said to it and to the earth, ‘
Come, willingly or unwillingly!’ They said, ‘We come obediently.’
But disobeying Allah in His second orders and wills, i.e. Tashri'i ones, is possible. Because indeed, those orders are not Existential, rather are Contractual.(It should be said that the Tashri'i orders are not Existential, but are according to the existential facts and truths).
The religious orders are indeed the Tashri'i orders of Allah. Satan and others can only disobey Allah in these cases.
Also, keep in mind that disobeying Allah in the Tashri'i orders does not mean overcoming Allah. He says in Holy Quran, 29:4
Do those who commit misdeeds suppose that they have outmaneuvered Us? Evil is the judgement that they make.
So, satan only can disobey Allah in His Tashri'i orders which are indeed contractual. Also, disobeying Him in these cases doesn't mean overcoming. So if satan disobeys Allah, this doesn't mean Allah is not Omnipotent. He can will that satan doesn't disobey Him. But because of the goal for which this world has created, He doesn't do it(, not can not do it). Indeed, satan is so weak to be named as the Lord of a thing.
4:76
Indeed the stratagems of Satan are always flimsy.
I can create something, and yet it can still fight against me. Take children in this world.
I have already explained how Allaah is All-Powerful but not Omnipotent
This is not a correct example. Because this creation is not like the creation of Allah. My example(the relation between the man and his/her imaginary creatures) was a better one and more similar to the creation of Allah and His relation with His creatures. Allah's creatures are not seprate from Him. But children are seprate from their parents.
Anyway, remember the difference between the Takwini and Tashri'i orders for this issue.
Allaah's Response in the verses you cite is to the person who says 'Please disregard my deeds, let me have another go'. Allaah's Response to this is 'No, I cannot wipe the slate clean so that you can go back and have another go. You cannot take back anything that you have done, for what's done is done.' And the barrier is that which prevents us from returning to life, which is of course lifted when we do return to life (resurrection is the return to life).
Where do I get this from? Allaah.
Wassalaam
That verse has another meaning. It says that, when the disbelievers die, they go to Barzakh world.
When a disbeliever dies, some truths will apear for him/her(see, Quran, 50:22), so that (s)he becomes awar that Allah is the only truth( أنه الحق ). So that (s)he becomes remorsefull from his/her bad previous doings and asks Allah to return him/her back from the Jahannam(Hell) of the Barzakh to this world so that (s)he may act righteously in what (s)he has left behind. But on contrary what you mentioned, Allah will not response that He can not do. No. He says to him/her, 'No, you will not act righteously in what you have left behind, if I return you back to the world. These are mere words that you says. Indeed, you are lying and if I do what you ask, you will continue your evil doings again in the world. So, I do not return you to the previous world.'
Keep in mind that dying is not becoming lifeless. It is indeed going from one world to another one, going from this world to the Barzakh world and then from it to the Resurrection world. Prophet Muhammad says,
You have not created for the inexistence, but for the remaining, and indeed you will be removed from a world to the another world.(ما خلقتم للفناء بل خلقتم للبقاء و انما تنتقلون من دار الی دار, source, Bihar Al-Anwar, v14,pg 409).
May Allah guide us to the truth...
