He was a faqih in legal opinion (ra'y), like his father Zayd well-known for that and the science of shares of inheritance. That is why Kharija had few hadiths, and many fatwas based on opinion. Because of his great knowledge of the shares of inheritance, he used to distribute people's inheritances according to the Book of Allah Almighty. Mus'ab ibn 'Abdullah said, "Kharija and Talha ibn 'Abdu'r-Rahman gave fatwa in their time. People accepted their statements and they distributed people's inheritance - houses, palm-trees and property – and they wrote out documents for people." In addition to his knowledge, fiqh and fatwa and his connection to people at the beginning of his life, Kharija was one of the devout worshippers of Madina. Worship moved him at the end of his life to withdraw and be alone, which is why not much of his fiqh and knowledge spread.
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