I have been looking into theories about reconstructing the history of the 7th Century and the origins of Islam. I however do believe the traditional Biography of Muhammad is fairly grounded in real history, unlike Jay Smith.
And the thesis I shall provide here doesn't even matter much to if the early Arab Empire was already distinctly "Muslim" or not, my theories on that I get into elsewhere. This is just specifically about what they did on The Temple Mount.
The current Dome of the Rock and Al Aqsa Mosque were both originally built by Abd al-Malik the third Umayyad Caliph between 690 and 705 AD, that's pretty indisputably agreed on by everyone. The question of whether or not the Arabs built some kind of earlier Mosque on the Temple Mount is difficult to answer since everything written on the subject from the Muslim POV is centuries later, including that account of Umar and Sophronius which many Gihon Spring Temple location supporters misunderstand.
There are however some contemporary 7th Century Christian sources, and one Jewish source. Here is a link quoting a number of them gathered together by Hoyland in 1997.
https://web.archive.org/web/20210211093519/http://www.christianorigins.com/islamrefs.html
There are Four primarily I want to quote, but first let me provide some context.
Byzantine Christians of Late Antiquity, and probably all the other mainstream types of Christians who existed at that time, on the subject of the possibly of a Third Jewish Temple being built had the exact opposite opinion of modern Dispensationalist Evangelicals. They not only weren't expecting it but they believed God would never allow it. So if they saw it happening they would have to either deny it, or interpret it as inherently negative. Like how today many Anti-Semitic Post Tribbers pretty much believe the Third Temple itself will be the Abomination of Desolation.
Meanwhile I have on my other Blog documented that the Quran is actually a Zionist book, it affirms Israel's right to the Promised Land and expects their return. The parts that seem Anti-Semitic exist in the context of the Arabs' conflict with Jews living in Arabia. I believe Muhammad probably never intended his united Arab state to expand west of the Jordan River (or East/North of the Euphrates for that matter). None the less when Umar did conquer Judea, even under the most traditional view of what happened he allowed The Jews to live in Jerusalem again after 500 years of Rome (both Pagan and Christian) banning them from the city.
Also on the use of the word "Mosque" in these passages, if that even is an accurate translation. It should be remembered that in the Quran itself the word Mosque does not mean the specific type of Muslim worship building we're used to today, but rather just means a Sacred site. The most popular interpretation of the Night Journey Sura is that the "Farthest Mosque" is the site of the Temple in Jerusalem even though no building of any kind stood there at the time.
So let's start with the witness of Sophronius the Patriarch of Jerusalem who died in 638 AD.
[In a work originally composed by John Moschus (d. 619), but expanded by Sophronius (d. ca. 639), actually found only in an addition of the Georgian translation, the following entry appears, concerning a construction dated by tradition at 638, i.e., soon after the capture of Jerusalem ca. 637. It appears in a portion concerning Sophronius as recounted on the authority of his contemporary, the archdeacon Theodore, and may have been written down ca. 670.]
the godless Saracens entered the holy city of Christ our Lord, Jerusalem, with the permission of God and in punishment for our negligence, which is considerable, and immediately proceeded in haste to the place which is called the Capitol. They took with them men, some by force, others by their own will, in order to clean that place and to build that cursed thing, intended for their prayer and which they call a mosque (midzgitha). (Pratum spirituale, 100-102 [p. 63])
I notice how hostile the Christians are to their Arab conquerors seems to depend on their sect of Christianity, the "Nestorians" like Ishoyahb and John bar Pankaye got along with them just fine. At any rate this reference doesn't tell us much about what's being built, but by "the Capitol" he almsot certainly means the City's highest peak, The Temple Mount, after all Hadrian's Temple bult there was called the Temple of Jupiter Capitolinus.
The second reference shall be the Coptic Apocalypse of Pseudo-Shenute from about 644 AD.
The Persians . . . will go down to Egypt and much killing will accompany them. They shall seize the wealth of the Egyptians and sell their children for gold, so harsh is the persecution and oppression of the Persians. Many masters will become slaves and many slaves masters. Woe to Egypt on account of the Persians. Many masters will become slaves and many slaves masters. Woe to Egypt on account of the Persians, for they will take the church vessels and drink wine from them before the altar without fear or anxiety. They will rape the women before their husbands. There shall be great distress and anguish, and of those that survive a third will die of grief and misery.
Then after a while the Persians will depart from Egypt and there shall arise the Deceiver, who will enter upon the king of the Romans and will be entrusted by him with headship of both the military commanders and the bishops. He shall enter Egypt and undertake many tasks; he shall take possession of Egypt and its provinces, and build ditches and forts, and order that the walls of the towns in the deserts and wastelands be [re-]built. He shall destroy the East and the West, then he shall combat the pastor, the archbishop in Alexandria entrusted with the Christians resident in the land of Egypt. They will expel him and he will flee southwards until he arrives, sad and dispirited, at your monastery. And when he comes here, I shall return him and place him on his seat once more.
After that shall arise the sons of Ishmael and the sons of Esau, who hound the Christians, and the rest of them will be concerned to prevail over and rule all the world and to [re-]build the Temple that is in Jerusalem. When that happens, know that the end of times approaches and is near. The Jews will expect the Deceiver and will be ahead of the [other] peoples when he comes. When you see the [abomination of] desolation of which the prophet Daniel spoke standing in the holy place, [know that] they are those who deny the pains which I received upon the cross and who move freely about my church, fearing nothing at all. (Ps.-Shenute, Vision, 340-41 [pp. 280-281])
Since the King of the Romans here is certainly Heraclius, my first instinct was that the "Deceiver" being referred to was Sergius Patriarch of Constantinople being condemned for the Monothelite controversy, but the Coptic perspective made me doubt that. Since the author would have considered Benjamin I the legitimate Bishop of Alexandria this Deceiver could fit Cyrus of Alexandria who was indeed given both Ecclesiastical and Military authority in Egypt. John of Niku was another Egyptian of the period who tied his hostility towards Cyrus into how he talked about the Arab conquest.
The last detail of that account could sound like it's saying the Arabs of this time already said Jesus didn't die on The Cross. But in the context of how Divine Impassability was what largely drove Nestorius to develop his view of the Incarnation, this could make sense to me as a criticism of Nestorianism. Just as Ishoyahb III saying "those who say that God, Lord of all, suffered and died" is a Nestorian criticism of Cyrilian Christianity and not opposition to the doctrine of the Crucifixion or Incarnation.
Arculf a pilgrim from the 670s.
In that famous place where once stood the magnificently constructed Temple, near the eastern wall, the Saracens now frequent a rectangular house of prayer which they have built in a crude manner, constructing it from raised planks and large beams over some remains of ruins. This house can, as it is said, accomodate at least 3000 people. (Adomnan, De locis sanctis 1.1.14.186 [p. 221])
However the most crucial witness to my theory is the Jewish one, Simon bar Yohai in the 680s.
The second king who arises from Ishmael will be a lover of Israel. He restores their breaches and the breaches of the Temple. He hews Mount Moriah, makes it level and builds a mosque (hishtahawaya) there on the Temple rock, as it is said: "Your nest is set in the rock." (Simon ben Yohai, Secrets, 79 [p. 311])
Not only did some Christians see this as a rebuilding of the Temple from a hostile POV, but Jews also celebrated it as a rebuilding of The Temple. Meanwhile the Rectangular shape shows this was being built more like Solomon's Temple then like the Octagonal Dome we see there now.
This witness has actually effected my opinion on the Dome of the Rock being the Temple Site. Having a Jewish pre Dome of the Rock witness to The Temple being on a Rock really lessens how unlikely I found that possibility previously.
Still technically it is the Al Aqsa Mosque that is in it's name claiming to be the "Farthest Mosque" of the Night Journey. And the Crusaders called that Mosque the Temple of Solomon and the Dome of the Rock the Temple of The Lord.
However archeologically we know that where the Al Aqsa Mosque is was Herod's southern expansion of The Temple complex, the Royal Stoa, so the least likely place on the Mount for the The Temple itself to have been.
