Imam Abou Abdellah (Pbuh) said: "Ya'qoub was inflicted with Yousuf because once he slaughtered a fat sheep and one of his needy companions had nothing to eat. Ya'qoub didn’t offer him food and so he was inflicted with Yousuf. After that, his speaker used to call upon people every morning "He who is not fasting is invited to have breakfast with Ya'qoub." and every evening: "He who is fasting is invited to have dinner with Ya'qoub."
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Stated in Tafseer Kanz Al-Daqa'eq Book.
