R. Yonah studied under R. Yirmiyah and eventually became the head of the academy in Tiberias. He appears to have been a close colleague of R. Yose b. Zevida. When he heard of the death of this colleague's' son, R. Yonah fasted.
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Rebbi Jonah said, it is not written, “hail to him who gives to the needy,” but (Ps. 41:2): “Hail to him who is considerate to the needy;” this refers to him who fulfills this commandment intelligently. How did Rebbi Jonah do it? When he saw a son of a prominent family who had lost his property, he used to say to him: My son, since I heard that an inheritance fell to you at another place, take and you will pay back. When he had taken it, he said to him, it is a gift.