Shaykhul Islam ibn Taymiyah wrote in “Furqan Bayna Awliya Rahman wa Awliya Shaytan” Eng tran p 155:

“It is not a perquisite for a Waliy of Allah that he be free of sin or error, instead it is possible that some knowledge of the Shariah be unknown to him or some aspects of the religion confuse him to the extent that he think that some matters commanded by Allah are actually prohibited by Him. It is possible that he think that some occurences are from the miracles of the Awliya of Allah, the Exalted, while in reality they are from Shaytan who has disguised them and (hence succeeded in fooling him) so that he is unaware that they are from him due to his lesser ranking. None of this ejects a person from being included amongst the ranks of the Awliya of Allah, the Exalted. This is because Allah, the Glorious and Exalted, has overlooked this nation’s genuine errors, acts of forgetfulness and those things they were coerced into doing”

Shaykh Salih Aal Shaykh wrote in explanation of it, p 160, Maktabah Dar Al-Hijaz:

“This distinction is a fundation (Asl) in the topic of Wilayah, and it is that it is not a condition for the Wali not to make a mistake at all or that he never errs, or that he doesn’t have confusion in some important matters in Aqidah or in the Islamic law, or that he does not have a deficiency in acting in some matters, and it is not a condition for the Wali that he becomes complete…”

On p 340, Shaykh Salih Aal Shaykh explained 2 kinds of Karamat and how they can in little instances occur for people who have mistakes and innovations against disbelievers:

“First category: Karamah Ilmiyah (in knowledge)

Second: Karamah from direction of power and influence.

As for Ilm (knowledge), it can be in knowledge with unveiling (Ilmiyan Kashfiyan), by being made aware of things hidden, such as the knowledge of Abu Bakr about the sex of newborn, he saw what was in the womb of the woman, so As-Siddiq (rad) said: “A girl is shown to me”

It can be in knowledge by listening, so he hears what other do not hear, such as Saariyah when he heard the speech of Omar (rad), or hearing things that habitude does not make listen with long distance, as the Karamah that occurred for Omar (rad)…

As for the second, it is from perspective of Qudrah (power) and influence, meaning that he is capable of doing thins other cannot do, or he can have an influence in the creation others cannot have. When we say he has influence or he is capable, IT IS ALLAH MAKING THIS OCCUR (IJRA ullahi) ON HIS HANDS, as we have defined Karamah with our saying: “What Allah makes occurring from Khawariq Adaat (things above natural habitude/breaking natural laws) upon the hands of the Wali, and the MEANING IS NOT THAT HE GIVES HIM POWER IN INFLUENCE as stipulated by extreme Sufis until they reached level of saying for the one they believe to be Wali that he says about something “Be” and it is. IT IS ONLY ALLAH MAKING THESE OCCUR UPON HIS HANDS AS AN HONOUR. IT DOES NOT MEAN THAT HE HAD A PERPETUAL POWER OF INFLUENCE OR TRANSFORMING THINGS OR WHAT IS SIMILAR TO IT…

When this has become clear, the Karamah can occur upon the hands of other than a Wali. The basis is that it occurs only to the obedient, the pious Wali, the fearful believer, and it can occur for the disobedient and it CAN OCCUR FOR THE INNOVATOR, and these instances are little, it is only to strengthen his faith because of its weakness or the strengthen those with him against their enemies, due to the foundation of faith in them against the disbelieving enemy, or because he is defending the religion so he is given honour because of his defence of the religion in opposition to the polytheist and disbeliever.

Hence the occurrence of Karamat or Khawariq for a group who is innovator became difficult for some, such as what is mentioned from the occurrence of Karamat in Afghanistan to some people in their fight against infidels (Tr: Russians in 80), and a group came saying: “this is not correct as some of them are innovators, they have some forms of polytheism”, so they would deny, and the other group would reply: “We saw with our eyes”, so they were declared truthful, so confusion spread whether they are lying or truthful.

The rule of Ahlus Sunnah in this chapter is that these were fighting infidels, and they were fighting disbelievers enemies of Allah, and these were Muslims who were attributing themselves to the foundation of Islam, so they could be granted something from the Khawariq, not for them, but for the prevalence of the religion that was with them against their enemies, and this happens in the domain of debates, a Mutazili can debate a Christian so he is honoured with some forms of evidences that come to his mind, and this because of the foundation of the religion that is with him in opposition to the Christian polytheist, and he can be an Ashari debating for instance and likewise, so a Karamah that occurs for a servant, it is proper to examine it and ponder over it, and one should not rush to approve or deny”

Shaykh Salih Aal Shaykh wrote on p 165 speaking of different kinds of Karamat e Awliya:

“As the one related to knowledge (Ilmiyah): similar to what is proven from Abu Bakr that he looked at the belly of his wife and said: “I am shown a girl”IT IS MENTIONED FROM A GROUP OF SALIHIN AND PEOPLE OF KNOWLEDGE THAT THEY HAVE KASHF ILMI OF WHAT ALLAH SENDS ILHAM TO THEM, SO THEY KNOW WHAT IS IN THE WOMB, meaning after a time, so they will say that there is a Male a Female in it….

The Muhaqiq Adil ibn Muhammad Mursi Rifai wrote on this narration: “Malik in Muwatta (1438), AbdurRazaq in his Musannaf (9/101), Bayhaqi in Al-Kubra (6/169) and Lalikai in Karamat Awliya p 116 from the way of Urwah ibn Zubair from Aishah”