It is narrated from Sa'id bin Jubayr (may Allah have mercy on him) that a man from the Jews of the people of al-Hirah met me and asked me: Which of the two terms did Musa (peace be upon him) complete? I said: I do not know; tomorrow I will go to Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both). So I went to him and asked him, and he replied that Musa (peace be upon him) completed the term that was the longer and the purer. I informed the Jew, and he said: That companion of yours is a scholar.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب المساقاة / 11637