Umair bin Ishaq (may Allah have mercy on him) says that once I was with Hazrat Imam Hasan (may Allah be pleased with him) when on the way we met Hazrat Abu Hurairah (may Allah be pleased with him). He said, "Show me the part of your body where the Prophet Muhammad (peace and blessings be upon him) kissed you, so that I may also have the honor of kissing it." Upon this, Hazrat Imam Hasan (may Allah be pleased with him) lifted his shirt and Hazrat Abu Hurairah (may Allah be pleased with him) kissed his navel.