Shaykh Ahmad al-Tijani (God be pleased with him) said:

Generally, all who obtained the science of philosophy leaped into ignorance, while claiming that they had reached the pinnacle of knowledge. But they were far removed from the Knowledge of God and the awareness of His Majesty.

They expounded to the common folk that whoever did not know their science was as if he knew nothing. The souls of the common folk followed them, inclined towards bounty, for they saw how they were exalted in the hearts of the commoners, kings, and princes. On account of following this whirlwind, which differed from the righteous forefathers (salaf) without any excuse or restraint, the true knowledge of tawhid sent with the Messengers was forgotten. Those who sought the tawhid of the Messengers came to reject the tawhid of the philosophers as poison for the Sufis and gnostics. And indeed, those who sought the tawhid of the philosophers became as poison for theology itself.

As for the interjection into the discipline of theology by gnostics such as Imam al-Ash’ari and al-Sanusi and they like, may God be pleased with them, is was only their desire for kindness with the common folk. When it was (argued) that (disputes over) the tawhid of the Messengers cannot be answered except by the sword, they answered that the common people could accept the command of God by their own volition if they were given foundational rational proofs (for the correct tawhid). They saw this was better than the sword, for the one forced by the sword does not enter the religion except under compulsion and force. So this was the reason for their interjection into the science of theology.