Al-Hasan (may Allah have mercy on him) said that a man came to Sayyiduna Ali (may Allah be pleased with him) in Kufah and stayed with him for some days. Then he mentioned a dispute of his, so Sayyiduna Ali (may Allah be pleased with him) sent him out of his house, because the Prophet (peace and blessings be upon him) forbade "that a party to a dispute be hosted unless his opponent is with him."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب آداب القاضي / 20471