who is ibn Qaasim, Maliki?

[Nasrollah]

someone knows the biography of Abdur Rahman ibn Al-Qaasim

[Imperium]

From Aisha Bewley's website


This scholar was one of the companions of Malik who had a tremendous influence in recording his school since he was the source for Sahnun in his record of the teaching of Malik. In the school of Malik he has the same position as Muhammad ibn al-Hasan ash-Shaybani has in the school of Abu Hanifa. There is a complete correspondence between the two men. Both of them transmitted the school and made free use of ijtihad. Ibn al-Qasim had opinions which differed from those of his shaykh, Malik, so that it was said that he was dominated by opinion. Ibn 'Abdu'l-Barr said of him, "He was a faqih dominated by opinion. He was a righteous, poor, steadfast man."

He met Malik after Ibn Wahb and kept his company for a long time – about twenty years. He learned his fiqh. He also met al-Layth, 'Abdu'l-'Aziz ibn al-Majishun and Muslim ibn Khalid al-Zanji. Many people related from him and consulted him about Malik's fatwas. Ibn Wahb used to say, "If you want this business – meaning the fiqh of Malik – you must have Ibn al-Qasim. He is unique in it." His transmission of the Muwatta' is the soundest and Sahnun learned the contents of the Mudawwana, the most comprehensive collection of Maliki fiqh, from him. Thus he can be considered as the main transmitter of Maliki fiqh, for the Mudawwana is its chief source.

He was a generous and abstemious man. He did not accept the stipends of any ruler and he said, "There is no good in the proximity of rulers." He frequented them at first, but then he kept away from them. He died in 191 at the age of 63.

[Nasrollah]

why the salafis said that He is not trustworthy and Mudawwanah is dhaeef? specially about raf al yadayn