except Allah.’ ‘So know that there is no deity except Allah.’ For this reason, the point of dispute between the messengers and their peoples was made to concern Allah’s oneness:

‘That is because, when Allah alone was invoked, you disbelieved; but when partners were associated with Him, you believed.’
Ghāfir 12.

‘When Allah alone is mentioned, the hearts of those who do not believe in the Hereafter recoil in aversion.’
Al-Zumar 45.

‘And when you mention your Lord alone in the Quran, they turn their backs in aversion.’
Al-Isrā’ 46.”

He said:

“The speculative theologians followed one approach to establishing the existence of the Maker: reasoning from things that come into being to an Originator and Maker. The ancient philosophers followed another approach: reasoning from the contingency of contingent things to a determining factor that favors one of the two possibilities.”

I say:

The ancient philosophers did not follow this second approach. Rather, it was followed by Ibn Sīnā and those who agreed with him. But al-Shahrastānī and others like him do not know the doctrines of Aristotle and the ancient philosophers, since they rely chiefly on Ibn Sīnā’s books for their accounts of philosophy.