Assalaamu alaykum wa rahmatullaahi wa barakaatuhu. There is something which I have been trying really hard to understand for years now; it is regarding the order of creation. I have seen the fatwas here say that the Earth was created, then the seven Heavens, and then the Earth was spread and everything within the Earth was created, including the mountains. Here is my confusion:
{And He placed on the earth firmly set mountains over its surface, and He blessed it and determined therein its [creatures'] sustenance in four days without distinction - for [the information] of those who ask. Then He directed Himself to the heaven while it was smoke and said to it and to the earth, "Come [into being], willingly or by compulsion." They said, "We have come willingly. And He completed them as seven heavens within two days and inspired in each heaven its command. And We adorned the nearest heaven with lamps and as protection. That is the determination of the Exalted in Might, the Knowing.} [Quran 41:10-12]
{Are you a more difficult creation or is the heaven? Allah constructed it. He raised its ceiling and proportioned it. And He darkened its night and extracted its brightness. And after that He spread the earth. He extracted from it its water and its pasture. And the mountains He set firmly} [Quran 79:27-32]
As you can see above, Surat Fussilat mentions the mountains before the Heaven, while Surat An-Nazi‘aat mentions the mountains after the heaven. I heard an argument in some other places regarding the word "Thumma". I have seen in some way that the "Thumma" mentioned in Quran 2:29 and 41:11 is not there to indicate chronological order but to contrast between the heavens and earth. Could this be the correct view? Please help me to understand this, Allah willing. May Allah reward you.

All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad is His slave and Messenger.

First of all, we thank you for contacting us, and we advise you to be concerned with important issues of faith, such as the fundamentals of faith, the actions of the heart, acts of worship, and other matters of religion that you need. As for the issues whose details are not useful to know, then it is better not to be concerned with them, especially if one is just beginning to seek Islamic knowledge or is not a specialist in the matter. The issue which you enquired about belongs to that category. It is a problematic issue, and there is no great benefit in investigating it.

Ash-Shihaab said in his commentary on al-Baydhaawi, "Know that the creation of the heavens and what is in it, and the earth and what is in it, in terms of the sequence as to which one was first and which one was next, there are verses and hadiths about it which are contradictory, and people since the time of the Companions until now found difficulties about it and tried to reconcile between them, but they have different ways of reconciling between them."

Al-Baydhaawi profusely elaborated on the issue, as well as Al-Aloosi in his Tafseer (exegesis), so please refer to them.

As for what you mentioned, that (thumma) is not for the chronological order in the verses in Surat Al-Baqarah and Surat Fussilat, then this is among the answers of those who held the view that the creation of the heavens happened before the creation of the earth. Al-Qurtubi said, "(Thumma) signifies the sequence of informing about it, and not the sequence of the matter itself (that He is informing about)."

As for the confusion that you mentioned regarding the creation of the mountains, then it is indeed problematic to say that the creation of the earth preceded the creation of the heavens, and that spreading the earth – which includes creating the mountains and making them firm – happened after the creation of the heavens.

This is what Ibn ‘Abbaas narrated in a Mu‘allaq hadith (a hadith in which one or more narrators from the beginning of its chain are missing) reported by Al-Bukhaari, but what is contrary to this was also narrated from him in a Mawqoof hadith (a hadith with a chain of narrators terminating at the Companion level) and a Marfoo‘ hadith (a hadith directly attributed to the Prophet, sallallaahu ‘alayhi wa sallam), and that the creation of the heavens took place after the creation of the earth, and after it was completely spread out. This statement removes the confusion which you mentioned, and the words (after that) in the verse: {And after that He spread the earth} [Quran 79:30] signify the level/degree, and not the chronological order.

Ibn ‘Ashoor said, "It is possible that the words (after that) are metaphorical, meaning that the level of what was mentioned after it is lower than what was mentioned before it, such as the saying of Allah (which means): {Cruel, after that an illegitimate pretender.} [Quran 68:13]"

Likewise, according to the first view, it is possible to solve the confusion about (thumma) in the verse: {Then He directed Himself to the heaven while it was smoke} [Quran 41:11] by saying that (thumma), here, is not for the chronological order; rather, it is the sequence of informing about it. As regards (thumma) in the verse from Surat Al-Baqarah, it refers to the chronological order.

For more benefit, please refer to fatwas 342076 and 302260.

Allah knows best.